Question

What is the sum of the first 7 terms of the series


-8+16-32+64-...?

Answer 1

It should be -344

Explanation:

The common ratio is -2.

Using this common ratio you can find the remaining 3 numbers.

Which are: 64(-2) = -128, -128(-2) = 256, and 256(-2)= -512

-8+16-32+64-128+256-512 = -344