Fraction/Exponent Q

[dtloxy]

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

in essence figure out what m is...

-17
-18
-34
-35
-36

Hell of a way to start a practice test... I guessed (wrong). Afterward, I saw the right answer, but can't rationalize what was provided. Clearly, I'm missing some basic rule that will relieve my confusion. Any guidance?

[satyaking]

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

in essence figure out what m is...

-17
-18
-34
-35
-36

Hell of a way to start a practice test... I guessed (wrong). Afterward, I saw the right answer, but can't rationalize what was provided. Clearly, I'm missing some basic rule that will relieve my confusion. Any guidance?

for such problems ,try to bring the numbers into their prime factors in both the sides of equality and then equate the exponents of respective prime factors to get the unknown value(e.g. m).

in this instance,
1/(5^m . 2^36)=1/(2^36 . 5^35)

comparing the exponents of 5, we get m=35

hope it hepls

[dtloxy]

Yes, Satyaking, that does help a lot, and I'm slapping my forehead. Thank you very much.

[RonPurewal]

please search the forum

gmat-prep-1-5-m-1-4-18-1-2-10-35-t1976.html