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Exponent Problem

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Junior | Next Rank: 30 Posts
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by jakesing » Mon Jul 06, 2009 10:06 am
4^11=(2^2)^11=2^22

So you have 5^21x2^22=2x10^n

Divide both sides by 2, you'll get:

5^21x2^21=10^n.

Use the property that says (x^n)x(y^n)=(xy^n), you get:

10^21=10^n.

n=21.

Hope that helps!
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by learnitboy » Mon Jul 06, 2009 10:11 am
4^11=2^22=2*2^21

2*2^21*5^21=2*(2*5)^21=2*10^21 so n=21
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by ghacker » Tue Jul 07, 2009 9:09 am
n = 21

n depends on the powers of 5 ( since the powers of 2 > powers of 5)
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