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
Accepted Solution
A:
Answer:-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.