A shopkeeper sells (12) notebooks on the first day and (4) more notebooks each next day. How many notebooks are sold in (6) days?
Answer and explanation
Correct answer: 132
The daily notebook sales form the AP \(12,16,20,24,28,32\). Here, \(a=12\), \(d=4\), and \(n=6\). Thus, \(S_6=\frac{6}{2}[2(12)+(6-1)4]=3(44)=132\). Therefore, the correct answer is 132. Option 128 may result from omitting the last term or making an addition error. Exam tip: In AP word problems, first identify \(a\), \(d\), and \(n\), then apply the formula for \(S_n\).
Frequently asked questions
What is the correct answer to this question?
132
Why is this the correct answer?
The daily notebook sales form the AP \(12,16,20,24,28,32\). Here, \(a=12\), \(d=4\), and \(n=6\). Thus, \(S_6=\frac{6}{2}[2(12)+(6-1)4]=3(44)=132\). Therefore, the correct answer is 132. Option 128 may result from omitting the last term or making an addition error. Exam tip: In AP word problems, first identify \(a\), \(d\), and \(n\), then apply the formula for \(S_n\).
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Arithmetic Progressions (AP). Topic: Word problems based on APs.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
