Question

The number of terms in an AP is even; the sum of the odd terms in it is 24 and that the even terms is 30. If the last term exceeds the first term by 10 1/2 hen the number of terms in the AP is:

(A)  4 

(B)  8 

(C)  12 

(D)  16

Answer 1

Correct option  (B)  8

Let number of terms = 2n, n ∈ N. Given

Now subtracting Eq. (5) from Eq. (4), we get

Now from Eq. (3)

Thus, the number of terms = 2 × 4 = 8