An infinite geometric series has a sum of 100 and a common ratio of 4/5. what is the first term of the series?

geometric-series
common-ratio

#1

An infinite geometric series has a sum of 100 and a common ratio of 4/5. what is the first term of the series?

Answer:

Here we got special case of geometric series with |r| = 4/5 <1
The infinite sum for such common ratio has the following value:
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