What is the sum of the first eight terms of the series?

(-800) + (-200) + (-50) + (-12.5) + ...

Round the answer to two decimal places.

-1066.68

-1066.65

-1066.60

-1062.50

-1066.65 to 2 decimal places.

Step-by-step explanation:

(-800) + (-200) + (-50) + (-12.5) + ...

This is a Geometric series with common ratio r = (-200) / ) / (-800) = 0.25 and first term a1 = - 800.

Sum of n terms = a1 * (1 - r^n) / (1 - r)

Sum of 8 terms = - 800 * (1 - 0.25^8) / (1 - 0.25)

= - 800 * 1.333313

= - 1066.65.

-1066.65

This is the correct answer! I just took the test! Good luck!