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Hi GMAT?,

There is a slight typo in your first problem statement. I have rephrased the question correctly.

Problem#1 (1/4)^18 x (1/5)^m = 1/2(10)^35. What is m?

(1/2^2)^18 x (1/5^m) = 1/2(2 x 5)^35 = 1/(2^1 x 2^35 x 5^35)

(1/2^36) x (1/5^m) = 1/(2^36 x 5^35)

Equating the exponents of 5, we obtain m = 35.


Problem#2. 2^x - 2^x-2 = 3(2^13)

2^x - 2^x-2 = 3(2^13)

2^x - (2^x)/2^2 = 3(2^13)

Factor 2^x,

2^x (1 - 1/4) = 3(2^13)

2^x * (3/4) = 3(2^13)

Multiple both sides by 4/3 to obtain:

2^x = 4 * 2^13 = 2^2 * 2^13 = 2^15

Equating the exponents, we obtain x = 15

Cheers,
Mark

Thanks for your help Mark, it is much appreciated.

I'm having alot of difficulty understanding these complex exponent and square root problems.

I don't have a maths background - I'm a medical doctor. I know the rules of exponents but find them difficult to apply in this type of situation.

Do you know of any good resources where I could get lots of pratice for this type of problem.

My exam is in 5 days - Maybe it would be best to just concentrate and try to improve what I already know rather then start learning diffcult maths.

What do you think?

it's OK with me since, i had seen those problems and knew the answers (& how to solve them)

but i am afraid for other readers who never seen the problems before might find some difficulty in understanding the problems let alone know the explanation.
its not me not you but the stupid computer's inablity to print/output the math equations/expressions.

so we might want to try something like this (with neat handwriting )


or may be we can try drawing in word document-use print screen tool - publish it on post as a picture file.

great efforts Mark.
thank you.

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