SOLUTION: How many terms are in the geometric sequence 8, 24, 72...648?
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Question 577920: How many terms are in the geometric sequence 8, 24, 72...648?
Found 2 solutions by stanbon, dfrazzetto:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
How many terms are in the geometric sequence 8, 24, 72...648?
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r = 24/8 = 3
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a(n) = ar^(n-1)
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8(3)^(n-1) = 648
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3^(n-1) = 81
3^(n-1) = 3^4
n-1 = 4
n = 5
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There are 5 terms.
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Cheers,
Stan H.
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Answer by dfrazzetto(283) (Show Source): You can put this solution on YOUR website!
A geometric sequence is a sequence in which the next terms are multiplied by a common value, in this case 3
8, 8x3=24, 24x3=72, etc
8, 24, 72, 216, 648
So, 5 terms
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