find the ratio of GP if the first term is 1 and the sum of third and fifth term is 90.

Sweta,

A geometric progression has a first term wihch is commonly called a and a common ratio commonly designeted r. What makes the progression "geometric" is that after the first term, each term is r times the previous term. Hence the progression is

a, ar, ar^{2}, ar^{3}, ar^{4}, ···

For your progression a = 1.

Can you complete the problem now?

Penny

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