Question

After inserting n A.M.’s between 2 and 38, the sum of the resulting progression is 200. The value of n is

• A. 10
• B. 8
• C. 9
• D. None of these

Answer 1

Answer: (B)

8

Answer 2

There will be (n + 2) terms in the resulting A.P.

$2,A_{1},A_{2},......,A_{n},38$

Sum of the progression $= \frac{n + 2}{2}(2 + 38)$

⇒ $200 = (n + 2) \times 20$

⇒$n = 8$