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by Anurag@Gurome » Fri Mar 02, 2012 5:35 pm
jzw wrote:If (1/5)^m x (1/4)^18 = 1/2(10)^36 then m = ?

How do you solve this?
It seems there is a typo in the question, it should be: If (1/5)^m x (1/4)^18 = 1/2(10)^35 then m = ?

(1/5)^m x (1/2²)^18 = 1/2(2 * 5)^35
(1/5)^m x (1/2)^36 = 1/{2(2^35) * (5)^35}
(1/5)^m x (1/2)^36 = 1/{(2^36) * (5)^35}
Since bases are the same, so equating the exponents, we get,
m = 35
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by jzw » Fri Mar 02, 2012 6:34 pm
Hey - ur right, it was a 35 and not a 36. It was fuzzy, a friend of mine who took a practice test took a snapshot and emailed it to me. Thanks!!!
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by krusta80 » Fri Mar 02, 2012 7:11 pm
jzw wrote:If (1/5)^m x (1/4)^18 = 1/2(10)^36 then m = ?

How do you solve this?
(1/5)^m x (4)^-18 = 1/2(10)^36

1/(5^m*2^36) = 1/(2^37*5^36)

2*5^36 = 5^m

m = log5(2)+36

The solution method is the same with the typo, but you will never see log5 on the GMAT.
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