Question

The geometric sequence has 10 members. The sum of members with even indexes is 682 and with impartial is 1364. What is the first member and quotient of this sequence?

Answer 1

sum of all terms except the first one is 682 + 1364 = 2016

looks like first term = 2 and common ratio = 2

becuase sum oi 10 terms is a1 (r^10 - 1) / (r - 1)
and if we plug in fisrt term a1 = 2 and r = 2 we get

2 * (2^10 - 1) / (2 -1) we get 2046

so first member is 2 and common ratio = 2