OG product of fractions and neg exponents Q

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(1/2)^(-3)*(1/4)^(-2)*(1/16)^(-1) = ?

A. 1/2^(-48)
B. 1/2^(-11)
C. 1/2^(-6)
D. 1/8^(-11)
E. 1/8^(-6)

B

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by Brent@GMATPrepNow » Tue Jul 25, 2017 7:54 pm
AbeNeedsAnswers wrote:(1/2)^(-3)*(1/4)^(-2)*(1/16)^(-1) = ?

A. 1/2^(-48)
B. 1/2^(-11)
C. 1/2^(-6)
D. 1/8^(-11)
E. 1/8^(-6)

B
NOTE:
1/4 = (1/2)^2
1/16 = (1/2)^4
So, (1/2)^(-3) x (1/4)^(-2) x (1/16)^(-1) = (1/2)^(-3) x ((1/2)^2)^(-2) x ((1/2)^4)^(-1)
= (1/2)^(-3) x (1/2)^(-4) x (1/2)^(-4)
= (1/2)^-11

Answer: B
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by Scott@TargetTestPrep » Mon Aug 14, 2017 2:09 pm
AbeNeedsAnswers wrote:(1/2)^(-3)*(1/4)^(-2)*(1/16)^(-1) = ?

A. 1/2^(-48)
B. 1/2^(-11)
C. 1/2^(-6)
D. 1/8^(-11)
E. 1/8^(-6)

B
Let's simplify the given expression by making all factors have the same base:

(1/2)^(-3) * (1/4)^(-2) * (1/16)^(-1)

(1/2)^(-3) * (1/2)^((2)(-2)) * (1/2)^((4)(-1))

(1/2)^(-3) * (1/2)^(-4) * (1/2)^(-4)

(1/2)^(-3 - 4 - 4) = (1/2)^-11

Answer: B

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