Question

19. The sum of the three successive terms in the AP series is 48. The product of the first and last term is
252. so d =
(A) 2
(B) 4
(C) 8
(D) 16​

Answer 1

Answer:

Let the 3 consecutive terms be a-d,a and a+d

According to 1st condition

a-d+a+a+d=48

3a=48

: .a=16

According to 2nd condition

(a-d)(a+d)=252

(16-d)(16+d)=252

by formula of (a+b)(a-b)=a*2-b*2, we get

16*2-d*2=252

256-d*2=252

: . -d*2=252-255

=-4

: .d*2=4

: .d=2