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stuck on this exponent problem?

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by camitava » Tue Oct 30, 2007 1:20 am
davy420, does ur Qs -
(1/5)^m * (1/4)^18 = 1/2(10)^35
mean
(1/5)^m * (1/4)^18 = 1/(2(10)^35)?
If so, then my approach will be -
5 ^ -m * 2 ^ -36 = 1/(2 ^ 36 * 5 ^ 35)
or, = 2 ^ -36 * 5 ^ -35
So m = 35.
Are u getting me davy420?
Correct me If I am wrong


Regards,

Amitava
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by davy420 » Tue Oct 30, 2007 11:20 am
yes you are correct? The answer is 35 but I doidn't know how to solve for m. Thanks alot
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by ricosh13 » Tue Mar 16, 2010 11:04 am
This problem is from a while ago but I came across it and I am not following one of the steps:

5 ^ -m * 2 ^ -36 = 1/(2 ^ 36 * 5 ^ 35)
or, = 2 ^ -36 * 5 ^ -35
So m = 35.
Are u getting me davy420?

I don't understand how he went simplified the second half of the equation 2(10)^-35 to 2^-36 * 5^-35
hopefully someone can spell it out a little clearer, thanks
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by harshavardhanc » Tue Mar 16, 2010 11:55 am
ricosh13 wrote:This problem is from a while ago but I came across it and I am not following one of the steps:


I don't understand how he went simplified the second half of the equation 2(10)^-35 to 2^-36 * 5^-35
hopefully someone can spell it out a little clearer, thanks

I'll give it a try....
(1/5)^m * (1/4)^18 = 1/2(10)^35

start with the right had side of the equation.

Split 10 as 2*5

So you get 2* (2*5)^35

in all, there are are 36 twos and 35 fives on the RHS.


Now, come to the left hand side of the eq. you can view 4 as 2^2.

So, you have 36 twos and m fives on the LHS.

Equate them.

You get M as 35.

Hope it is clearer now. :)
Regards,
Harsha
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by ricosh13 » Tue Mar 16, 2010 1:13 pm
ahhh why didn't I see this... thought 2(10)^-35= 2^-35*2^-35*5^-35

just couldn't understand how that became his simplified version but I think I got it Noe
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