What will be the sum of the first (5) terms of the AP (60,54,48,\ldots)?
Answer and explanation
Correct answer: 240
In this AP, the first term is \(a=60\) and the common difference is \(d=54-60=-6\). The first five terms are \(60,54,48,42,36\), and their sum is \(60+54+48+42+36=240\). Therefore, 240 is the correct answer. A result such as 250 can arise from not handling the decreasing terms or the common difference \(-6\) correctly. Exam tip: remember to use a negative sign for \(d\) in a decreasing AP.
Frequently asked questions
What is the correct answer to this question?
240
Why is this the correct answer?
In this AP, the first term is \(a=60\) and the common difference is \(d=54-60=-6\). The first five terms are \(60,54,48,42,36\), and their sum is \(60+54+48+42+36=240\). Therefore, 240 is the correct answer. A result such as 250 can arise from not handling the decreasing terms or the common difference \(-6\) correctly. Exam tip: remember to use a negative sign for \(d\) in a decreasing AP.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Arithmetic Progressions (AP). Topic: Finding the sum of the first $n$ terms of an AP.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
