SOLUTION: Find the sum of an infinite geometric series where a1 = 180, and the common ratio is r = 3∕4 ?

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Question 1205650: Find the sum of an infinite geometric series where a1 = 180, and the common ratio is r = 3∕4 ?
Found 2 solutions by math_tutor2020, ikleyn:
Answer by math_tutor2020(3817) About Me  (Show Source):
You can put this solution on YOUR website!

a = 180 = first term
r = 3/4 = 0.75 = common ratio

Since -1 < r < 1 is true when r = 0.75, we can use the infinite geometric sum formula shown below.
S = a/(1 - r)
S = 180/(1 - 0.75)
S = 720


Answer: 720

Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
.
Find the sum of an infinite geometric series where a1 = 180, and the common ratio is r = 3∕4
~~~~~~~~~~~~~~~~~~~ 

This sum is equal to

    a1%2F%281-r%29 = 180%2F%281-3%2F4%29 = 180%2F%28%281%2F4%29%29 = 4*180 = 720.    ANSWER

Solved.