SOLUTION: 2^m times 5^n = 128000000. what does m+n equal? A/13 B/15 C/16 D/17 E/19

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Question 422063: 2^m times 5^n = 128000000. what does m+n equal?
A/13
B/15
C/16
D/17
E/19
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
2^m times 5^n = 128000000. what does m+n equal?
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Take the log of both sides to get:
m(log2) + nlog5 = log128,000,000
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Solve 2^x = 5
x = log2(5) = log(5)/log(2) = 2.321928
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solve 2^k = 128000000
k = log2(128000000) = log(128000000)/log(2) = 26.931569
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(2^m)*2^(2.321928n) = = 2^26.931569
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m + 2.321928n = 26.931569
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There is no one value for m+n
The variable vales form an infinite number of (n,m) pairs.
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Cheers,
Stan H.
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