If t and u are positive integers, what is the value of t^(-2)u^(-3) ?
(1) t^(-3)u^(-2) = 1/36
(2) t(u^(-1)) = 1/6
TUTUTUTUTUT
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IMO ans is E.
given t and u are both positive integers, there sum or differences can never be fractions.
both equations are just given to confuse.
I hope am correct.
given t and u are both positive integers, there sum or differences can never be fractions.
both equations are just given to confuse.
I hope am correct.
What if i have not yet beat the beast, I know i will beat it!!!!!!!!
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i go with E as well.. As the question says "INTEGERS" there is no way that their addition/subtraction will result in a Non integer..jimmiejaz wrote:IMO ans is E.
given t and u are both positive integers, there sum or differences can never be fractions.
both equations are just given to confuse.
I hope am correct.
- logitech
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That was the trap Cramya. I am glad you are still alive!!cramya wrote:I am getting C)
VALUE = 1/6*1/36
Made a mistake. THinking more about it only values possible for t and u ar 1 and 6 hence A)
LGTCH
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I get C.
Here is my approach.
Stmt 1:
1/ (t^3 u^2) = 1/36
insufficient coz we need to know 1 / (t^2 u^3)
Stmt 2:
t/u = 1/6.
Insufficient.
Combining:
Multiply stmt 1 by stmt 2.
we get 1/ (t^3 u^2) * t/u = 1/36 * 1/6
1/(t^2 u^3) = 1/6^3 a definite answer
So C is sufficient.
What is the OA.
thanks
-V
Here is my approach.
Stmt 1:
1/ (t^3 u^2) = 1/36
insufficient coz we need to know 1 / (t^2 u^3)
Stmt 2:
t/u = 1/6.
Insufficient.
Combining:
Multiply stmt 1 by stmt 2.
we get 1/ (t^3 u^2) * t/u = 1/36 * 1/6
1/(t^2 u^3) = 1/6^3 a definite answer
So C is sufficient.
What is the OA.
thanks
-V
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- Stuart@KaplanGMAT
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(1) let's start by making this less complicated.logitech wrote:If t and u are positive integers, what is the value of t^(-2)u^(-3) ?
(1) t^(-3)u^(-2) = 1/36
(2) t(u^(-1)) = 1/6
t^(-3) is just 1/t^3... u^(-2) is just 1/(u^2).. so, we have:
(1/t^3)(1/u^2) = 1/36
taking the reciprocal of both sides:
(t^3)(u^2) = 36
Since we know that t and u are positive integers, we should be suspicious that there are limited possibilities. Let's break 36 down to primes:
36 = 2*2*3*3
Well, there's no way we're getting an integer cubed by using primes. Therefore, the only possible value for t is 1. Once we know that t has to be 1, u must be 6.
Since we know the values of t and u, we can answer any question about them: sufficient.
(2) simplifying, we get:
t/u = 1/6
Well, there's an infinite number of positive integers (e.g 1/6, 2/12, 3/18, ...) that fit that ratio and, since t and u appear in a different ratio in the question, each set of numbers will give us a different answer: insufficient.
(1) is sufficient, (2) isn't: choose (A).
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