# Math

4) The sum of an infinite geometric series is 100. The second term of the series is 24. Find two possibilities for a (the
first term) and r (the common ratio).
b. Given,
5 2 4 a a a    159
and
4 1 3 a a a    265
, find the terms of the sequence and give its explicit form

ONLY PART B

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2. 👎 0
3. 👁 26
1. a/(1-r) = 100
ar = 24
divide and you have
1/(r(1-r)) = 100/24
r = 2/5 or 3/5
a = 60 or 40

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2. 👎 0
posted by Steve

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