gmat prep exponents question

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by truplayer256 » Sun Apr 05, 2009 9:01 am
This question has been answered several times on this forum. I'll give it a try anyways.

(1/5)^(m)*(1/4)^(18)=1/2*10^35
1/5^(m)*1/4^(18)=1/2(5*2)^35
1/5^(m)*1/4^(18)=1/2*5^35*2^35
1/5^(m)*1/(2^2)^(18)=1/2^36*5^35 (Note: 2*2^35=2^36 since you add exponents when you're multiplying two numbers with simlar bases.)
1/5^(m)*1/2^(36)=1/2^(36)*5^35
The 1/2^(36)'s cancel and you're left with:
1/5^(m)=1/5^(35)
Therefore, m=35.