The first term of a geometric series is 124. The sum to infinity is 64 . Find the common ratio

Question

asked Feb 4, 2022 230k views

1 Answer

James Toomey · Answer 1 · 2022-02-09T19:17:44+0000

9514 1404 393

Answer:

-15/16

Explanation:

The sum of a geometric series with first term a1 is ...

S = a1/(1 -r)

Then the common ratio (r) is ...

r = 1 -a1/S

For the given values, the ratio is ...

r = 1 - 124/64 = -15/16

The common ratio is -15/16.