Exponent Question

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Exponent Question

by willywonka14 » Sun Jan 27, 2008 6:32 pm
Hi,
Im having trouble figuring this out...

2 exponent b = 48 exponent 5
____________
12 exponent 5


what is the value of b?

Can anyone explain how to solve this?

Thanks in advance,
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by willywonka14 » Sun Jan 27, 2008 6:43 pm
sorry, should actually read:

2exponent b =

48 exponent 5
______________

12 expnent 5

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by simplyjat » Sun Jan 27, 2008 9:08 pm
I am not sure that you have posted the correct question...
"2 exponent b + 48 exponent 5 = 12 expnent 5"
simplyjat

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by Stuart@KaplanGMAT » Sun Jan 27, 2008 10:13 pm
I think the question should read:

If 2^b = (48^5)/(12^5), what's the value of b?

Let's start by simplifying the right side of the equation:

48^5 = (12^5)(4^5)

So, 48^5/12^5 = (12^5)(4^5)/12^5 = 4^5

To make the right side comparable to the left, let's do:

4^5 = (2^2)^5 = 2^(2*5) = 2^10

Now we have:

2^b = 2^10

and b=10.
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by sibbineni » Mon Jan 28, 2008 3:55 am
Yes I agree with stuart...

Suggest me if iam wrong.

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by willywonka14 » Mon Jan 28, 2008 5:14 am
thanks so much...I get it now..much appreciated.