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

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1 Answer
Apr 16, 2018

-625

Explanation:

We have a geometric series which follows an=arn1

a=first term=500
r=common ratio=a2a2=100500=15

Sum of a geometric series is given by:
Sn=a1(1rn1r)

S8=500(10.2810.2)=55(0.999997440.8)=500(1.2499968)=624.9984625