The third,fourth and eight term of A.P form first three consecutive term of G.P.if the sum of the first ten term of A.P is 85.calculate the first term of both A.P and G.P,common ratio and sum of 5 term of G.P

Answer 1

just write it as math, and then solve. If the AP has 1st term a, and the GP has first term g, then

a+2d = g
a+3d = gr
a+7d = gr^2
10/2 (2a+d) = 85