समांतर श्रेणी \(6,9,12,\ldots\) के पहले (14) पदों का योग ज्ञात कीजिए।
Find the sum of the first (14) terms of the arithmetic progression \(6,9,12,\ldots\).
#ap
#sum
#first_n_terms
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A (347)
B (357)
C (367)
D (377)
Explanation opens after your attempt
Step 1
Concept
Here (a=6), (d=3), and (n=14), so \(S_{14}=357\). First identify (a), (d), and (n).
Step 2
Why this answer is correct
The correct answer is B. (357). Here (a=6), (d=3), and (n=14), so \(S_{14}=357\). First identify (a), (d), and (n).
Step 3
Exam Tip
यहाँ (a=6), (d=3), (n=14) है, इसलिए \(S_{14}=357\)। पहले (a), (d), (n) पहचानना सबसे जरूरी है।
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यदि किसी समांतर श्रेणी में पहला पद (4), अंतर (5) और पदों की संख्या (13) है, तो पहले (13) पदों का योग कितना होगा?
If an arithmetic progression has first term (4), common difference (5), and (13) terms, what is the sum of the first (13) terms?
#ap
#sum
#formula
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A (422)
B (432)
C (442)
D (452)
Explanation opens after your attempt
Step 1
Concept
Using (S_n=\frac{n}{2}[2a+(n-1)d]), we get \(S_{13}=442\). Write ((n-1)d) carefully in the formula.
Step 2
Why this answer is correct
The correct answer is C. (442). Using (S_n=\frac{n}{2}[2a+(n-1)d]), we get \(S_{13}=442\). Write ((n-1)d) carefully in the formula.
Step 3
Exam Tip
सूत्र (S_n=\frac{n}{2}[2a+(n-1)d]) से \(S_{13}=442\) मिलता है। सूत्र में ((n-1)d) ध्यान से लिखें।
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समांतर श्रेणी \(15,19,23,\ldots\) के पहले (10) पदों का योग क्या है?
What is the sum of the first (10) terms of the arithmetic progression \(15,19,23,\ldots\)?
#ap
#sum
#last_term
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A (310)
B (320)
C (330)
D (340)
Explanation opens after your attempt
Step 1
Concept
The tenth term is (51), so (S_{10}=\frac{10}{2}(15+51)=330). Finding the last term first is an easy method.
Step 2
Why this answer is correct
The correct answer is C. (330). The tenth term is (51), so (S_{10}=\frac{10}{2}(15+51)=330). Finding the last term first is an easy method.
Step 3
Exam Tip
दसवाँ पद (51) है, इसलिए (S_{10}=\frac{10}{2}(15+51)=330)। अंतिम पद निकालकर योग लेना आसान तरीका है।
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पहले (22) प्राकृतिक संख्याओं का योग कितना है?
What is the sum of the first (22) natural numbers?
#natural_numbers
#ap_sum
#easy
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A (243)
B (253)
C (263)
D (273)
Explanation opens after your attempt
Step 1
Concept
The sum of the first (n) natural numbers is (\frac{n(n+1)}{2}), so the answer is (253). Put the value of (n) directly in such questions.
Step 2
Why this answer is correct
The correct answer is B. (253). The sum of the first (n) natural numbers is (\frac{n(n+1)}{2}), so the answer is (253). Put the value of (n) directly in such questions.
Step 3
Exam Tip
पहले (n) प्राकृतिक संख्याओं का योग (\frac{n(n+1)}{2}) होता है, इसलिए (253) मिलेगा। ऐसे प्रश्न में सीधे (n) का मान लगाएँ।
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पहले (15) विषम प्राकृतिक संख्याओं का योग ज्ञात कीजिए।
Find the sum of the first (15) odd natural numbers.
#odd_numbers
#sum
#ap
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A (215)
B (220)
C (225)
D (230)
Explanation opens after your attempt
Step 1
Concept
The sum of the first (n) odd numbers is \(n^2\), so \(15^2=225\). This short formula saves time in exams.
Step 2
Why this answer is correct
The correct answer is C. (225). The sum of the first (n) odd numbers is \(n^2\), so \(15^2=225\). This short formula saves time in exams.
Step 3
Exam Tip
पहले (n) विषम संख्याओं का योग \(n^2\) होता है, इसलिए \(15^2=225\)। यह छोटा सूत्र परीक्षा में समय बचाता है।
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पहले (19) सम प्राकृतिक संख्याओं का योग कितना होगा?
What will be the sum of the first (19) even natural numbers?
#even_numbers
#ap_sum
#easy
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A (370)
B (380)
C (390)
D (400)
Explanation opens after your attempt
Step 1
Concept
The sum of the first (n) even numbers is (n(n+1)), so \(19\times20=380\). Even numbers start from \(2,4,6,\ldots\).
Step 2
Why this answer is correct
The correct answer is B. (380). The sum of the first (n) even numbers is (n(n+1)), so \(19\times20=380\). Even numbers start from \(2,4,6,\ldots\).
Step 3
Exam Tip
पहले (n) सम संख्याओं का योग (n(n+1)) होता है, इसलिए \(19\times20=380\)। सम संख्याएँ \(2,4,6,\ldots\) से शुरू होती हैं।
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यदि किसी समांतर श्रेणी का पहला पद (8), अंतिम पद (62) और कुल पद (10) हैं, तो योग क्या होगा?
If the first term of an arithmetic progression is (8), the last term is (62), and there are (10) terms, what is the sum?
#first_last
#ap_sum
#formula
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A (330)
B (340)
C (350)
D (360)
Explanation opens after your attempt
Step 1
Concept
Using (S_n=\frac{n}{2}(a+l)), \(S_{10}=350\). If the last term is given, finding (d) is not needed.
Step 2
Why this answer is correct
The correct answer is C. (350). Using (S_n=\frac{n}{2}(a+l)), \(S_{10}=350\). If the last term is given, finding (d) is not needed.
Step 3
Exam Tip
(S_n=\frac{n}{2}(a+l)) से \(S_{10}=350\)। अंतिम पद दिया हो तो (d) निकालने की जरूरत नहीं होती।
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समांतर श्रेणी \(40,36,32,\ldots\) के पहले (8) पदों का योग ज्ञात कीजिए।
Find the sum of the first (8) terms of the arithmetic progression \(40,36,32,\ldots\).
#decreasing_ap
#sum
#negative_difference
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A (208)
B (216)
C (224)
D (232)
Explanation opens after your attempt
Step 1
Concept
The eighth term is (12), so (S_8=\frac{8}{2}(40+12)=208). In a decreasing progression, take the difference as negative.
Step 2
Why this answer is correct
The correct answer is A. (208). The eighth term is (12), so (S_8=\frac{8}{2}(40+12)=208). In a decreasing progression, take the difference as negative.
Step 3
Exam Tip
आठवाँ पद (12) है, इसलिए (S_8=\frac{8}{2}(40+12)=208)। घटती श्रेणी में अंतर ऋणात्मक लें।
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समांतर श्रेणी \(7,12,17,\ldots\) के पहले (9) पदों का योग कितना होगा?
What will be the sum of the first (9) terms of the arithmetic progression \(7,12,17,\ldots\)?
#ap_sum
#nine_terms
#average
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A (232)
B (243)
C (254)
D (265)
Explanation opens after your attempt
Step 1
Concept
The ninth term is (47), so (S_9=\frac{9}{2}(7+47)=243). With an odd number of terms, the middle term can also check the sum.
Step 2
Why this answer is correct
The correct answer is B. (243). The ninth term is (47), so (S_9=\frac{9}{2}(7+47)=243). With an odd number of terms, the middle term can also check the sum.
Step 3
Exam Tip
नौवाँ पद (47) है, इसलिए (S_9=\frac{9}{2}(7+47)=243)। विषम पदों में मध्य पद से भी योग जाँचा जा सकता है।
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एक सभागार में सीटों की पंक्तियाँ \(9,12,15,\ldots\) के क्रम में हैं। पहले (12) पंक्तियों में कुल कितनी सीटें होंगी?
In an auditorium, rows of seats follow \(9,12,15,\ldots\). How many seats will there be in the first (12) rows?
#word_problem
#seats
#ap_sum
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A (296)
B (306)
C (316)
D (326)
Explanation opens after your attempt
Step 1
Concept
Here (a=9), (d=3), and (n=12), so there will be (306) seats. In word problems, convert the pattern into an arithmetic progression.
Step 2
Why this answer is correct
The correct answer is B. (306). Here (a=9), (d=3), and (n=12), so there will be (306) seats. In word problems, convert the pattern into an arithmetic progression.
Step 3
Exam Tip
यहाँ (a=9), (d=3), (n=12) है, इसलिए कुल (306) सीटें होंगी। शब्द-प्रश्न में क्रम को समांतर श्रेणी में बदलें।
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यदि \(S_6=72\) और \(S_{12}=252\) है, तो सातवें से बारहवें पदों का योग कितना है?
If \(S_6=72\) and \(S_{12}=252\), what is the sum of the (7)th to (12)th terms?
#partial_sum
#ap_sum
#subtraction
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A (160)
B (170)
C (180)
D (190)
Explanation opens after your attempt
Step 1
Concept
The sum of the (7)th to (12)th terms is \(S_{12}-S_6=180\). Subtract partial sums to find the sum of middle terms.
Step 2
Why this answer is correct
The correct answer is C. (180). The sum of the (7)th to (12)th terms is \(S_{12}-S_6=180\). Subtract partial sums to find the sum of middle terms.
Step 3
Exam Tip
सातवें से बारहवें पदों का योग \(S_{12}-S_6=180\) है। बीच के पदों का योग निकालने के लिए आंशिक योग घटाएँ।
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समांतर श्रेणी \(3,10,17,\ldots\) के पहले (11) पदों का योग क्या है?
What is the sum of the first (11) terms of the arithmetic progression \(3,10,17,\ldots\)?
#ap_sum
#eleven_terms
#last_term
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A (418)
B (428)
C (438)
D (448)
Explanation opens after your attempt
Step 1
Concept
The eleventh term is (73), so (S_{11}=\frac{11}{2}(3+73)=418). Finding the last term correctly is the key step.
Step 2
Why this answer is correct
The correct answer is A. (418). The eleventh term is (73), so (S_{11}=\frac{11}{2}(3+73)=418). Finding the last term correctly is the key step.
Step 3
Exam Tip
ग्यारहवाँ पद (73) है, इसलिए (S_{11}=\frac{11}{2}(3+73)=418)। अंतिम पद सही निकालना मुख्य चरण है।
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किसी समांतर श्रेणी के पहले (8) पदों का औसत (27) है। इन (8) पदों का योग कितना है?
The average of the first (8) terms of an arithmetic progression is (27). What is the sum of these (8) terms?
#average
#ap_sum
#direct
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A (206)
B (216)
C (226)
D (236)
Explanation opens after your attempt
Step 1
Concept
Sum equals average \(\times\) number of terms, so \(27\times8=216\). If the average is given, the long formula is not needed.
Step 2
Why this answer is correct
The correct answer is B. (216). Sum equals average \(\times\) number of terms, so \(27\times8=216\). If the average is given, the long formula is not needed.
Step 3
Exam Tip
योग (=) औसत \(\times\) पदों की संख्या, इसलिए \(27\times8=216\)। औसत मिले तो लंबा सूत्र जरूरी नहीं।
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समांतर श्रेणी \(18,22,26,\ldots\) के पहले (15) पदों का योग ज्ञात करें।
Find the sum of the first (15) terms of the arithmetic progression \(18,22,26,\ldots\).
#ap_sum
#fifteen_terms
#formula
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A (680)
B (690)
C (700)
D (710)
Explanation opens after your attempt
Step 1
Concept
The fifteenth term is (74), so (S_{15}=\frac{15}{2}(18+74)=690). The sum can also be found using the average of the first and last terms.
Step 2
Why this answer is correct
The correct answer is B. (690). The fifteenth term is (74), so (S_{15}=\frac{15}{2}(18+74)=690). The sum can also be found using the average of the first and last terms.
Step 3
Exam Tip
पंद्रहवाँ पद (74) है, इसलिए (S_{15}=\frac{15}{2}(18+74)=690)। पहले और अंतिम पद का औसत लेकर भी योग मिल जाता है।
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एक विद्यार्थी प्रतिदिन \(4,8,12,\ldots\) अभ्यास प्रश्न हल करता है। पहले (10) दिनों में कुल कितने प्रश्न हल होंगे?
A student solves \(4,8,12,\ldots\) practice questions per day. How many questions will be solved in the first (10) days?
#word_problem
#practice
#ap_sum
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A (200)
B (210)
C (220)
D (230)
Explanation opens after your attempt
Step 1
Concept
This is the sum of the first (10) multiples of (4), so the total is (220) questions. Treat the number of days as (n).
Step 2
Why this answer is correct
The correct answer is C. (220). This is the sum of the first (10) multiples of (4), so the total is (220) questions. Treat the number of days as (n).
Step 3
Exam Tip
यह (4) के पहले (10) गुणजों का योग है, इसलिए कुल (220) प्रश्न होंगे। दिनों की संख्या को (n) मानें।
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यदि किसी समांतर श्रेणी में (a=20), (d=-3), और (n=7) है, तो पहले (7) पदों का योग कितना होगा?
If an arithmetic progression has (a=20), (d=-3), and (n=7), what is the sum of the first (7) terms?
#negative_difference
#ap_sum
#easy
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A (77)
B (87)
C (97)
D (107)
Explanation opens after your attempt
Step 1
Concept
The seventh term is (2), and (S_7=\frac{7}{2}(20+2)=77). Do not make a sign error with negative (d).
Step 2
Why this answer is correct
The correct answer is A. (77). The seventh term is (2), and (S_7=\frac{7}{2}(20+2)=77). Do not make a sign error with negative (d).
Step 3
Exam Tip
सातवाँ पद (2) है और (S_7=\frac{7}{2}(20+2)=77)। ऋणात्मक (d) में चिन्ह की गलती न करें।
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समांतर श्रेणी \(25,30,35,\ldots\) के पहले (12) पदों का योग कितना है?
What is the sum of the first (12) terms of the arithmetic progression \(25,30,35,\ldots\)?
#ap_sum
#twelve_terms
#last_term
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A (610)
B (620)
C (630)
D (640)
Explanation opens after your attempt
Step 1
Concept
The twelfth term is (80), so (S_{12}=\frac{12}{2}(25+80)=630). Keep both the last term and (n) correct.
Step 2
Why this answer is correct
The correct answer is C. (630). The twelfth term is (80), so (S_{12}=\frac{12}{2}(25+80)=630). Keep both the last term and (n) correct.
Step 3
Exam Tip
बारहवाँ पद (80) है, इसलिए (S_{12}=\frac{12}{2}(25+80)=630)। अंतिम पद और (n) दोनों को सही रखें।
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पहले (13) विषम प्राकृतिक संख्याओं का योग क्या होगा?
What will be the sum of the first (13) odd natural numbers?
#odd_numbers
#ap_sum
#pattern
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A (159)
B (169)
C (179)
D (189)
Explanation opens after your attempt
Step 1
Concept
The sum of the first (n) odd numbers is \(n^2\), so \(13^2=169\). Remember this pattern for odd numbers.
Step 2
Why this answer is correct
The correct answer is B. (169). The sum of the first (n) odd numbers is \(n^2\), so \(13^2=169\). Remember this pattern for odd numbers.
Step 3
Exam Tip
पहले (n) विषम संख्याओं का योग \(n^2\) है, इसलिए \(13^2=169\)। विषम संख्याओं के लिए यह पैटर्न याद रखें।
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यदि \(a_n=3n+2\) है, तो पहले (5) पदों का योग ज्ञात कीजिए।
If \(a_n=3n+2\), find the sum of the first (5) terms.
#nth_term
#ap_sum
#sequence
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A (50)
B (55)
C (60)
D (65)
Explanation opens after your attempt
Step 1
Concept
The first (5) terms are (5,8,11,14,17), whose sum is (55). If \(a_n\) is given, list the terms to check.
Step 2
Why this answer is correct
The correct answer is B. (55). The first (5) terms are (5,8,11,14,17), whose sum is (55). If \(a_n\) is given, list the terms to check.
Step 3
Exam Tip
पहले (5) पद (5,8,11,14,17) हैं, जिनका योग (55) है। \(a_n\) दिया हो तो पद लिखकर जाँचें।
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एक बचत योजना में हर महीने जमा राशि \(200,250,300,\ldots\) रुपये है। पहले (8) महीनों की कुल राशि कितनी होगी?
In a savings plan, the monthly deposit is \(200,250,300,\ldots\) rupees. What is the total amount for the first (8) months?
#word_problem
#savings
#ap_sum
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A (2900)
B (3000)
C (3100)
D (3200)
Explanation opens after your attempt
Step 1
Concept
Here (a=200), (d=50), and (n=8), so the total is (3000) rupees. In money questions, keep the unit in mind.
Step 2
Why this answer is correct
The correct answer is B. (3000). Here (a=200), (d=50), and (n=8), so the total is (3000) rupees. In money questions, keep the unit in mind.
Step 3
Exam Tip
यहाँ (a=200), (d=50), (n=8) है, इसलिए कुल (3000) रुपये होंगे। राशि वाले प्रश्न में इकाई भी लिखें।
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समांतर श्रेणी \(2,9,16,\ldots\) के पहले (13) पदों का योग क्या है?
What is the sum of the first (13) terms of the arithmetic progression \(2,9,16,\ldots\)?
#ap_sum
#thirteen_terms
#easy
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A (542)
B (552)
C (562)
D (572)
Explanation opens after your attempt
Step 1
Concept
The thirteenth term is (86), so (S_{13}=\frac{13}{2}(2+86)=572). Use ((n-1)d) when finding the last term.
Step 2
Why this answer is correct
The correct answer is D. (572). The thirteenth term is (86), so (S_{13}=\frac{13}{2}(2+86)=572). Use ((n-1)d) when finding the last term.
Step 3
Exam Tip
तेरहवाँ पद (86) है, इसलिए (S_{13}=\frac{13}{2}(2+86)=572)। अंतिम पद निकालते समय ((n-1)d) का उपयोग करें।
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यदि किसी समांतर श्रेणी में \(S_5=65\) और \(S_{11}=242\) है, तो छठे से ग्यारहवें पदों का योग कितना है?
If an arithmetic progression has \(S_5=65\) and \(S_{11}=242\), what is the sum of the (6)th to (11)th terms?
#partial_sum
#ap_sum
#easy
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A (167)
B (177)
C (187)
D (197)
Explanation opens after your attempt
Step 1
Concept
The sum of the (6)th to (11)th terms is \(S_{11}-S_5=177\). The difference of partial sums gives the answer directly.
Step 2
Why this answer is correct
The correct answer is B. (177). The sum of the (6)th to (11)th terms is \(S_{11}-S_5=177\). The difference of partial sums gives the answer directly.
Step 3
Exam Tip
छठे से ग्यारहवें पदों का योग \(S_{11}-S_5=177\) है। आंशिक योगों का अंतर सीधे उत्तर देता है।
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पहले (17) सम प्राकृतिक संख्याओं का योग ज्ञात कीजिए।
Find the sum of the first (17) even natural numbers.
#even_numbers
#sum
#ap
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A (296)
B (306)
C (316)
D (326)
Explanation opens after your attempt
Step 1
Concept
The sum of the first (n) even numbers is (n(n+1)), so \(17\times18=306\). Do not confuse (n) with the last even number.
Step 2
Why this answer is correct
The correct answer is B. (306). The sum of the first (n) even numbers is (n(n+1)), so \(17\times18=306\). Do not confuse (n) with the last even number.
Step 3
Exam Tip
पहले (n) सम संख्याओं का योग (n(n+1)) है, इसलिए \(17\times18=306\)। (n) को अंतिम सम संख्या न समझें।
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समांतर श्रेणी \(60,55,50,\ldots\) के पहले (7) पदों का योग कितना है?
What is the sum of the first (7) terms of the arithmetic progression \(60,55,50,\ldots\)?
#decreasing_ap
#ap_sum
#first_last
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A (305)
B (315)
C (325)
D (335)
Explanation opens after your attempt
Step 1
Concept
The seventh term is (30), so (S_7=\frac{7}{2}(60+30)=315). The same sum formula works for a decreasing progression.
Step 2
Why this answer is correct
The correct answer is B. (315). The seventh term is (30), so (S_7=\frac{7}{2}(60+30)=315). The same sum formula works for a decreasing progression.
Step 3
Exam Tip
सातवाँ पद (30) है, इसलिए (S_7=\frac{7}{2}(60+30)=315)। घटती श्रेणी में भी वही योग सूत्र लगता है।
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किसी समांतर श्रेणी के पहले (6) पदों का योग (126) है। यदि पहले (6) पदों का औसत पूछा जाए, तो वह कितना होगा?
The sum of the first (6) terms of an arithmetic progression is (126). If the average of the first (6) terms is asked, what will it be?
#average
#ap_sum
#reverse
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A (19)
B (20)
C (21)
D (22)
Explanation opens after your attempt
Step 1
Concept
Average \(=\frac{126}{6}=21\). The average is found directly from the sum and number of terms.
Step 2
Why this answer is correct
The correct answer is C. (21). Average \(=\frac{126}{6}=21\). The average is found directly from the sum and number of terms.
Step 3
Exam Tip
औसत \(=\frac{126}{6}=21\)। योग और पदों की संख्या से औसत तुरंत मिल जाता है।
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समांतर श्रेणी \(13,18,23,\ldots\) के पहले (16) पदों का योग ज्ञात कीजिए।
Find the sum of the first (16) terms of the arithmetic progression \(13,18,23,\ldots\).
#ap_sum
#sixteen_terms
#last_term
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A (808)
B (816)
C (824)
D (832)
Explanation opens after your attempt
Step 1
Concept
The sixteenth term is (88), so (S_{16}=\frac{16}{2}(13+88)=808). For larger (n), find the last term first.
Step 2
Why this answer is correct
The correct answer is A. (808). The sixteenth term is (88), so (S_{16}=\frac{16}{2}(13+88)=808). For larger (n), find the last term first.
Step 3
Exam Tip
सोलहवाँ पद (88) है, इसलिए (S_{16}=\frac{16}{2}(13+88)=808)। बड़े (n) में अंतिम पद पहले निकालें।
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एक सीढ़ी में ईंटों की संख्या \(5,10,15,\ldots\) के क्रम में बढ़ती है। पहले (9) स्तरों में कुल कितनी ईंटें लगेंगी?
In a staircase, the number of bricks increases as \(5,10,15,\ldots\). How many bricks will be used in the first (9) levels?
#word_problem
#bricks
#ap_sum
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A (215)
B (225)
C (235)
D (245)
Explanation opens after your attempt
Step 1
Concept
This is the sum of the first (9) multiples of (5), so \(5\times45=225\). In word problems, treat levels as terms.
Step 2
Why this answer is correct
The correct answer is B. (225). This is the sum of the first (9) multiples of (5), so \(5\times45=225\). In word problems, treat levels as terms.
Step 3
Exam Tip
यह (5) के पहले (9) गुणजों का योग है, इसलिए \(5\times45=225\)। शब्द-प्रश्न में स्तरों को पद मानें।
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यदि समांतर श्रेणी का पहला पद (11), अंतिम पद (71) और पदों की संख्या (16) है, तो योग कितना होगा?
If the first term of an arithmetic progression is (11), the last term is (71), and the number of terms is (16), what is the sum?
#first_last
#ap_sum
#formula
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A (636)
B (646)
C (656)
D (666)
Explanation opens after your attempt
Step 1
Concept
(S_{16}=\frac{16}{2}(11+71)=656). If the first and last terms are given, use the shorter formula.
Step 2
Why this answer is correct
The correct answer is C. (656). (S_{16}=\frac{16}{2}(11+71)=656). If the first and last terms are given, use the shorter formula.
Step 3
Exam Tip
(S_{16}=\frac{16}{2}(11+71)=656)। पहला और अंतिम पद मिले हों तो छोटा सूत्र लगाएँ।
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समांतर श्रेणी \(8,16,24,\ldots\) के पहले (11) पदों का योग क्या है?
What is the sum of the first (11) terms of the arithmetic progression \(8,16,24,\ldots\)?
#multiples
#ap_sum
#eight
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A (518)
B (528)
C (538)
D (548)
Explanation opens after your attempt
Step 1
Concept
This is the sum of the first (11) multiples of (8), so \(8\times66=528\). For multiples, use the sum of natural numbers.
Step 2
Why this answer is correct
The correct answer is B. (528). This is the sum of the first (11) multiples of (8), so \(8\times66=528\). For multiples, use the sum of natural numbers.
Step 3
Exam Tip
यह (8) के पहले (11) गुणजों का योग है, इसलिए \(8\times66=528\)। गुणजों में प्राकृतिक संख्याओं के योग का उपयोग करें।
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पहले (28) प्राकृतिक संख्याओं का योग ज्ञात कीजिए।
Find the sum of the first (28) natural numbers.
#natural_numbers
#sum
#ap
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A (386)
B (396)
C (406)
D (416)
Explanation opens after your attempt
Step 1
Concept
\(\frac{28\times29}{2}=406\), so the sum is (406). The natural-number sum formula gives a quick answer.
Step 2
Why this answer is correct
The correct answer is C. (406). \(\frac{28\times29}{2}=406\), so the sum is (406). The natural-number sum formula gives a quick answer.
Step 3
Exam Tip
\(\frac{28\times29}{2}=406\), इसलिए योग (406) है। प्राकृतिक संख्याओं का योग सूत्र जल्दी उत्तर देता है।
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समांतर श्रेणी \(90,84,78,\ldots\) के पहले (6) पदों का योग कितना होगा?
What will be the sum of the first (6) terms of the arithmetic progression \(90,84,78,\ldots\)?
#decreasing_ap
#sum
#six_terms
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A (440)
B (450)
C (460)
D (470)
Explanation opens after your attempt
Step 1
Concept
The sixth term is (60), so (S_6=\frac{6}{2}(90+60)=450). In decreasing order, calculate the last term carefully.
Step 2
Why this answer is correct
The correct answer is B. (450). The sixth term is (60), so (S_6=\frac{6}{2}(90+60)=450). In decreasing order, calculate the last term carefully.
Step 3
Exam Tip
छठा पद (60) है, इसलिए (S_6=\frac{6}{2}(90+60)=450)। घटते क्रम में अंतिम पद की गणना ध्यान से करें।
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यदि किसी समांतर श्रेणी में (a=12), (d=8), और (n=10) है, तो \(S_{10}\) का मान क्या होगा?
If an arithmetic progression has (a=12), (d=8), and (n=10), what will be the value of \(S_{10}\)?
#ap_sum
#formula
#value
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A (470)
B (480)
C (490)
D (500)
Explanation opens after your attempt
Step 1
Concept
\(S_{10}=\frac{10}{2}[24+72]=480\). Do the calculation inside the bracket first.
Step 2
Why this answer is correct
The correct answer is B. (480). \(S_{10}=\frac{10}{2}[24+72]=480\). Do the calculation inside the bracket first.
Step 3
Exam Tip
\(S_{10}=\frac{10}{2}[24+72]=480\)। कोष्ठक के अंदर की गणना पहले करें।
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एक पौधारोपण अभियान में पौधे \(6,11,16,\ldots\) के क्रम में लगाए जाते हैं। पहले (10) दिनों में कुल कितने पौधे लगाए जाएँगे?
In a plantation campaign, plants are planted in the pattern \(6,11,16,\ldots\). How many plants will be planted in the first (10) days?
#word_problem
#plants
#ap_sum
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A (275)
B (285)
C (295)
D (305)
Explanation opens after your attempt
Step 1
Concept
The tenth term is (51), so the total is (S_{10}=\frac{10}{2}(6+51)=285) plants. The same sum formula works in real situations.
Step 2
Why this answer is correct
The correct answer is B. (285). The tenth term is (51), so the total is (S_{10}=\frac{10}{2}(6+51)=285) plants. The same sum formula works in real situations.
Step 3
Exam Tip
दसवाँ पद (51) है, इसलिए कुल (S_{10}=\frac{10}{2}(6+51)=285) पौधे होंगे। वास्तविक स्थितियों में भी योग सूत्र वही रहता है।
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समांतर श्रेणी \(1,6,11,\ldots\) के पहले (18) पदों का योग कितना है?
What is the sum of the first (18) terms of the arithmetic progression \(1,6,11,\ldots\)?
#ap_sum
#eighteen_terms
#common_difference
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A (773)
B (783)
C (793)
D (803)
Explanation opens after your attempt
Step 1
Concept
The eighteenth term is (86), so (S_{18}=\frac{18}{2}(1+86)=783). There are (n-1) common differences.
Step 2
Why this answer is correct
The correct answer is B. (783). The eighteenth term is (86), so (S_{18}=\frac{18}{2}(1+86)=783). There are (n-1) common differences.
Step 3
Exam Tip
अठारहवाँ पद (86) है, इसलिए (S_{18}=\frac{18}{2}(1+86)=783)। (n-1) अंतरों की संख्या होती है।
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यदि (S_n=\frac{n}{2}(a+l)), (a=14), (l=84), और (n=15) है, तो योग ज्ञात कीजिए।
If (S_n=\frac{n}{2}(a+l)), (a=14), (l=84), and (n=15), find the sum.
#first_last
#ap_sum
#easy
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A (715)
B (725)
C (735)
D (745)
Explanation opens after your attempt
Step 1
Concept
(S_{15}=\frac{15}{2}(14+84)=735). Take the average of the first and last terms and multiply by (n).
Step 2
Why this answer is correct
The correct answer is C. (735). (S_{15}=\frac{15}{2}(14+84)=735). Take the average of the first and last terms and multiply by (n).
Step 3
Exam Tip
(S_{15}=\frac{15}{2}(14+84)=735)। पहले और अंतिम पद का औसत लेकर (n) से गुणा करें।
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पहले (21) सम प्राकृतिक संख्याओं का योग क्या है?
What is the sum of the first (21) even natural numbers?
#even_numbers
#ap_sum
#formula
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A (452)
B (462)
C (472)
D (482)
Explanation opens after your attempt
Step 1
Concept
The sum of the first (21) even numbers is \(21\times22=462\). Use (n(n+1)) for even numbers.
Step 2
Why this answer is correct
The correct answer is B. (462). The sum of the first (21) even numbers is \(21\times22=462\). Use (n(n+1)) for even numbers.
Step 3
Exam Tip
पहले (21) सम संख्याओं का योग \(21\times22=462\) है। सम संख्याओं के लिए (n(n+1)) प्रयोग करें।
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समांतर श्रेणी \(17,20,23,\ldots\) के पहले (12) पदों का योग ज्ञात कीजिए।
Find the sum of the first (12) terms of the arithmetic progression \(17,20,23,\ldots\).
#ap_sum
#twelve_terms
#common_difference
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A (392)
B (402)
C (412)
D (422)
Explanation opens after your attempt
Step 1
Concept
The twelfth term is (50), so (S_{12}=\frac{12}{2}(17+50)=402). Find the last term and apply \(S_n\).
Step 2
Why this answer is correct
The correct answer is B. (402). The twelfth term is (50), so (S_{12}=\frac{12}{2}(17+50)=402). Find the last term and apply \(S_n\).
Step 3
Exam Tip
बारहवाँ पद (50) है, इसलिए (S_{12}=\frac{12}{2}(17+50)=402)। अंतिम पद निकालकर \(S_n\) लगाएँ।
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किसी समांतर श्रेणी के पहले (9) पदों का योग (198) है। पहले (9) पदों का औसत कितना होगा?
The sum of the first (9) terms of an arithmetic progression is (198). What will be the average of the first (9) terms?
#average
#ap_sum
#direct
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A (20)
B (21)
C (22)
D (23)
Explanation opens after your attempt
Step 1
Concept
Average \(=\frac{198}{9}=22\). Dividing the sum by the number of terms gives the average.
Step 2
Why this answer is correct
The correct answer is C. (22). Average \(=\frac{198}{9}=22\). Dividing the sum by the number of terms gives the average.
Step 3
Exam Tip
औसत \(=\frac{198}{9}=22\)। योग को पदों की संख्या से भाग देने पर औसत मिलता है।
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समांतर श्रेणी \(5,13,21,\ldots\) के पहले (7) पदों का योग कितना होगा?
What will be the sum of the first (7) terms of the arithmetic progression \(5,13,21,\ldots\)?
#ap_sum
#seven_terms
#average
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A (203)
B (205)
C (207)
D (209)
Explanation opens after your attempt
Step 1
Concept
The seventh term is (53), so (S_7=\frac{7}{2}(5+53)=203). With an odd number of terms, you can also check using the middle term.
Step 2
Why this answer is correct
The correct answer is A. (203). The seventh term is (53), so (S_7=\frac{7}{2}(5+53)=203). With an odd number of terms, you can also check using the middle term.
Step 3
Exam Tip
सातवाँ पद (53) है, इसलिए (S_7=\frac{7}{2}(5+53)=203)। विषम पदों में मध्य पद से भी जाँच सकते हैं।
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यदि किसी समांतर श्रेणी में \(S_4=44\) और \(S_{9}=189\) है, तो पाँचवें से नौवें पदों का योग कितना है?
If an arithmetic progression has \(S_4=44\) and \(S_9=189\), what is the sum of the (5)th to (9)th terms?
#partial_sum
#ap_sum
#subtraction
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A (135)
B (140)
C (145)
D (150)
Explanation opens after your attempt
Step 1
Concept
The sum of the (5)th to (9)th terms is \(S_9-S_4=145\). Subtract the given partial sums to get the answer.
Step 2
Why this answer is correct
The correct answer is C. (145). The sum of the (5)th to (9)th terms is \(S_9-S_4=145\). Subtract the given partial sums to get the answer.
Step 3
Exam Tip
पाँचवें से नौवें पदों का योग \(S_9-S_4=145\) है। दिए गए आंशिक योगों को घटाकर उत्तर लें।
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समांतर श्रेणी \(16,32,48,\ldots\) के पहले (6) पदों का योग ज्ञात करें।
Find the sum of the first (6) terms of the arithmetic progression \(16,32,48,\ldots\).
#multiples
#ap_sum
#six_terms
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A (336)
B (346)
C (356)
D (366)
Explanation opens after your attempt
Step 1
Concept
This is the sum of the first (6) multiples of (16), so \(16\times21=336\). For multiples, use \(1+2+\cdots+n\).
Step 2
Why this answer is correct
The correct answer is A. (336). This is the sum of the first (6) multiples of (16), so \(16\times21=336\). For multiples, use \(1+2+\cdots+n\).
Step 3
Exam Tip
यह (16) के पहले (6) गुणजों का योग है, इसलिए \(16\times21=336\)। गुणजों में \(1+2+\cdots+n\) का उपयोग करें।
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यदि किसी समांतर श्रेणी के पहले (10) पदों का योग (310) है और अंतिम पद (49) है, तो पहला पद कितना होगा?
If the sum of the first (10) terms of an arithmetic progression is (310), and the last term is (49), what is the first term?
#reverse_formula
#first_term
#ap_sum
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A (11)
B (12)
C (13)
D (14)
Explanation opens after your attempt
Step 1
Concept
From (310=\frac{10}{2}(a+49)), (a=13). Using the sum formula in reverse also appears in exams.
Step 2
Why this answer is correct
The correct answer is C. (13). From (310=\frac{10}{2}(a+49)), (a=13). Using the sum formula in reverse also appears in exams.
Step 3
Exam Tip
(310=\frac{10}{2}(a+49)) से (a=13)। योग सूत्र को उल्टा लगाना भी परीक्षा में आता है।
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समांतर श्रेणी \(75,70,65,\ldots\) के पहले (10) पदों का योग कितना है?
What is the sum of the first (10) terms of the arithmetic progression \(75,70,65,\ldots\)?
#decreasing_ap
#ap_sum
#ten_terms
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A (515)
B (525)
C (535)
D (545)
Explanation opens after your attempt
Step 1
Concept
The tenth term is (30), so (S_{10}=\frac{10}{2}(75+30)=525). The formula for \(S_n\) does not change in decreasing order.
Step 2
Why this answer is correct
The correct answer is B. (525). The tenth term is (30), so (S_{10}=\frac{10}{2}(75+30)=525). The formula for \(S_n\) does not change in decreasing order.
Step 3
Exam Tip
दसवाँ पद (30) है, इसलिए (S_{10}=\frac{10}{2}(75+30)=525)। घटते क्रम में भी \(S_n\) का सूत्र नहीं बदलता।
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एक दुकान में पैकेट \(7,14,21,\ldots\) की संख्या में रखे गए हैं। पहले (9) शेल्फों में कुल कितने पैकेट होंगे?
In a shop, packets are arranged in the numbers \(7,14,21,\ldots\). How many packets will there be in the first (9) shelves?
#word_problem
#packets
#ap_sum
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A (305)
B (315)
C (325)
D (335)
Explanation opens after your attempt
Step 1
Concept
This is the sum of the first (9) multiples of (7), so \(7\times45=315\). Treat the number of shelves as the number of terms.
Step 2
Why this answer is correct
The correct answer is B. (315). This is the sum of the first (9) multiples of (7), so \(7\times45=315\). Treat the number of shelves as the number of terms.
Step 3
Exam Tip
यह (7) के पहले (9) गुणजों का योग है, इसलिए \(7\times45=315\)। शेल्फों की संख्या को पदों की संख्या मानें।
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पहले (16) विषम प्राकृतिक संख्याओं का योग कितना है?
What is the sum of the first (16) odd natural numbers?
#odd_numbers
#ap_sum
#easy
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A (246)
B (256)
C (266)
D (276)
Explanation opens after your attempt
Step 1
Concept
The sum of the first (n) odd numbers is \(n^2\), so \(16^2=256\). This formula is worth remembering.
Step 2
Why this answer is correct
The correct answer is B. (256). The sum of the first (n) odd numbers is \(n^2\), so \(16^2=256\). This formula is worth remembering.
Step 3
Exam Tip
पहले (n) विषम संख्याओं का योग \(n^2\) होता है, इसलिए \(16^2=256\)। यह सूत्र याद रखने योग्य है।
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यदि (a=9), (d=9), और (n=8) है, तो समांतर श्रेणी के पहले (8) पदों का योग क्या होगा?
If (a=9), (d=9), and (n=8), what will be the sum of the first (8) terms of the arithmetic progression?
#multiples
#ap_sum
#nine
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A (304)
B (314)
C (324)
D (334)
Explanation opens after your attempt
Step 1
Concept
This is the sum of the first (8) multiples of (9), so \(9\times36=324\). If (a=d), the multiples method is faster.
Step 2
Why this answer is correct
The correct answer is C. (324). This is the sum of the first (8) multiples of (9), so \(9\times36=324\). If (a=d), the multiples method is faster.
Step 3
Exam Tip
यह (9) के पहले (8) गुणजों का योग है, इसलिए \(9\times36=324\)। (a=d) हो तो गुणज वाला तरीका तेज है।
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समांतर श्रेणी \(22,25,28,\ldots\) के पहले (14) पदों का योग ज्ञात कीजिए।
Find the sum of the first (14) terms of the arithmetic progression \(22,25,28,\ldots\).
#ap_sum
#fourteen_terms
#easy
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A (571)
B (581)
C (591)
D (601)
Explanation opens after your attempt
Step 1
Concept
The fourteenth term is (61), so (S_{14}=\frac{14}{2}(22+61)=581). Correct calculation of the last term gives the correct sum.
Step 2
Why this answer is correct
The correct answer is B. (581). The fourteenth term is (61), so (S_{14}=\frac{14}{2}(22+61)=581). Correct calculation of the last term gives the correct sum.
Step 3
Exam Tip
चौदहवाँ पद (61) है, इसलिए (S_{14}=\frac{14}{2}(22+61)=581)। अंतिम पद की सही गणना से योग सही मिलता है।
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किसी समांतर श्रेणी में पहला पद (31), अंतिम पद (13) और पदों की संख्या (7) है। योग कितना होगा?
In an arithmetic progression, the first term is (31), the last term is (13), and the number of terms is (7). What is the sum?
#first_last
#decreasing_ap
#ap_sum
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A (144)
B (154)
C (164)
D (174)
Explanation opens after your attempt
Step 1
Concept
(S_7=\frac{7}{2}(31+13)=154). The first term can be larger and the last term smaller.
Step 2
Why this answer is correct
The correct answer is B. (154). (S_7=\frac{7}{2}(31+13)=154). The first term can be larger and the last term smaller.
Step 3
Exam Tip
(S_7=\frac{7}{2}(31+13)=154)। पहला पद बड़ा और अंतिम पद छोटा हो सकता है।
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पहले (35) प्राकृतिक संख्याओं का योग क्या होगा?
What will be the sum of the first (35) natural numbers?
#natural_numbers
#ap_sum
#formula
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A (610)
B (620)
C (630)
D (640)
Explanation opens after your attempt
Step 1
Concept
\(\frac{35\times36}{2}=630\), so the sum is (630). Divide (n(n+1)) by (2).
Step 2
Why this answer is correct
The correct answer is C. (630). \(\frac{35\times36}{2}=630\), so the sum is (630). Divide (n(n+1)) by (2).
Step 3
Exam Tip
\(\frac{35\times36}{2}=630\), इसलिए योग (630) है। (n(n+1)) को (2) से भाग दें।
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समांतर श्रेणी \(10,18,26,\ldots\) के पहले (12) पदों का योग कितना होगा?
What will be the sum of the first (12) terms of the arithmetic progression \(10,18,26,\ldots\)?
#ap_sum
#twelve_terms
#final_check
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A (638)
B (648)
C (658)
D (668)
Explanation opens after your attempt
Step 1
Concept
The twelfth term is (98), so (S_{12}=\frac{12}{2}(10+98)=648). The average of the first and last terms is useful in sums.
Step 2
Why this answer is correct
The correct answer is B. (648). The twelfth term is (98), so (S_{12}=\frac{12}{2}(10+98)=648). The average of the first and last terms is useful in sums.
Step 3
Exam Tip
बारहवाँ पद (98) है, इसलिए (S_{12}=\frac{12}{2}(10+98)=648)। योग में पहले और अंतिम पद का औसत उपयोगी है।
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