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problem with exponents problem

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by ket » Wed May 27, 2009 10:50 am
IMO its 35

here is how i did it:

((1/5)^m)((1/4)^18)=(1/(2(10)^35))


5^(-m)*4^(-18)=2^(-1)*2^(-35)*5^(-35)

5^(-m)*2^(-36)=2^(-36)*5^(-35)

i.e. m=35


Hope it helps
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by eclaym2003 » Wed May 27, 2009 11:57 am
Thank you so much ... that definitely helped, you are a life saver. I actually like exponent problems but I get so frustrated when I run into ones that I can't figure out.
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Nice way

by rah_pandey » Thu May 28, 2009 1:33 am
Please remember in any exponent problem break it to simple factors and for integer soln the powers should match on both sides
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by smithde » Fri May 29, 2009 2:20 am
(1/5)^m (1/4)^18= 1/2(10)^35.
I think the r.h.s is 1/(2*10^35).This can be broken as follows :
1/(2*(2*5)^35) or
1/(2*(2^35)*(5^35)) or
1/((2^36)*(5^35)) or
1/((4^18)*(5^35))
Comparing this with the L.H.S m = 35

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