Practice focused topic-wise MCQs with answers and explanations for quick revision and exam preparation.
Difficulty select karke sirf is topic ke focused MCQs practice karein. Score, timer aur explanations student-friendly flow me milenge.
Showing 71-80 of 600 questions.
What will be the sum of the first (2) natural numbers?
B. (3)
पहली (2) प्राकृतिक संख्याएँ (1) और (2) हैं इसलिए योग (3) है। आधारभूत प्रश्नों में सूची बनाना सुरक्षित रहता है। / The first (2) natural numbers are (1) and (2), so the sum is (3). Listing terms is safe in basic questions.
Login to save your score, XP, coins and progress.
C. (55)
कुल ईंटें \(1+2+\cdots+10=55\) हैं। सीढ़ी जैसे पैटर्न में अक्सर \(S_n\) लगता है। / Total bricks are \(1+2+\cdots+10=55\). Stair-like patterns often use \(S_n\).
Login to save your score, XP, coins and progress.
Find the sum of the first (22) natural numbers.
A. (253)
\(S_{22}=\frac{22\times23}{2}=253\) है। सम संख्या (22) को आधा करके \(11\times23\) करें। / \(S_{22}=\frac{22\times23}{2}=253\). Halve the even number (22) and calculate \(11\times23\).
Login to save your score, XP, coins and progress.
If \(1+2+3+\cdots+n=28\), what is the value of (n)?
B. (7)
\(S_7=28\) क्योंकि \(\frac{7\times8}{2}=28\)। योग देखकर निकट प्राकृतिक संख्या चुनें। / \(S_7=28\) because \(\frac{7\times8}{2}=28\). Choose the nearby natural number by observing the sum.
Login to save your score, XP, coins and progress.
Which is the sum of the first (17) natural numbers?
C. (153)
\(S_{17}=\frac{17\times18}{2}=153\) है। विषम (n) में अगले सम गुणक को (2) से काटें। / \(S_{17}=\frac{17\times18}{2}=153\). For odd (n), divide the next even factor by (2).
Login to save your score, XP, coins and progress.
What will be the sum of \(1+2+3+\cdots+50\)?
D. (1275)
\(S_{50}=\frac{50\times51}{2}=1275\) होता है। बड़े (n) में सूत्र सीधे लगाएं। / \(S_{50}=\frac{50\times51}{2}=1275\). For larger (n), apply the formula directly.
Login to save your score, XP, coins and progress.
Which value is equal to the sum of the first (24) natural numbers?
C. (300)
\(S_{24}=\frac{24\times25}{2}=300\) है। (24) का आधा (12) लेकर \(12\times25\) करें। / \(S_{24}=\frac{24\times25}{2}=300\). Take half of (24) as (12) and calculate \(12\times25\).
Login to save your score, XP, coins and progress.
If \(S_n=120\) and \(S_n\) is the sum of the first (n) natural numbers, what is (n)?
C. (15)
\(S_{15}=120\) क्योंकि \(\frac{15\times16}{2}=120\)। ऐसे प्रश्नों में उत्तर को वापस सूत्र में जांचें। / \(S_{15}=120\) because \(\frac{15\times16}{2}=120\). In such questions, verify the answer back in the formula.
Login to save your score, XP, coins and progress.
What is the sum of the first (40) natural numbers?
C. (820)
\(S_{40}=\frac{40\times41}{2}=820\) है। (40) को (2) से भाग देकर \(20\times41\) करें। / \(S_{40}=\frac{40\times41}{2}=820\). Divide (40) by (2) and calculate \(20\times41\).
Login to save your score, XP, coins and progress.
C. (91)
कुल अंक \(1+2+\cdots+13=91\) हैं। अंतिम क्रम संख्या ही (n) का मान देती है। / The total score is \(1+2+\cdots+13=91\). The last rank gives the value of (n).
Login to save your score, XP, coins and progress.
Use Google login or mobile OTP. Admin can block users and control login providers.