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Find the sum of the first 7 terms of the following series, to the nearest integer. 150,60,24...

User Justinyoo
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1 Answer

2 votes

Answer:

250

Explanation:

The sum of the terms of a geometric series is given by the formula ...

Sn = a1×(1 -r^n)/(1 -r)

sum of n terms for first term a1 and common ratio r.

__

series sum

The given series has first term a1 = 150, and common ratio r = 60/150 = 2/5. Putting these values into the formula gives a sum of 7 terms that is ...

S7 = 150×(1 -(2/5)^7)/(1 -2/5) = 150((77997/78125)/(3/5))

S7 = 150×(25999/15625) = 249.5904

Rounded to the nearest integer, the sum of the first 7 terms is 250.

Find the sum of the first 7 terms of the following series, to the nearest integer-example-1
User Zishan Neno
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