SOLUTION: In a geometric sequence, the common ratio is -5. The sum of the first 3 terms is 147.What is the value of the first term in the sequence?
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Question 1115161: In a geometric sequence, the common ratio is -5. The sum of the first 3 terms is 147.What is the value of the first term in the sequence? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! In a geometric sequence, the common ratio is -5. The sum of the first 3 terms is 147.What is the value of the first term in the sequence?
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a + ar + ar^2 = 147
a(1+r+r^2) = 147
a(1-5+25) = 147
a = 147/21
a = 7
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Cheers,
Stan H.
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