stne wrote:
Bunuel wrote:
What is the value of a^-2*b^-3?
Note that we are not told that a and b are integers.
a^{-2}*b^{-3}=\frac{1}{a^2b^3}=? So, basically we need to find the value of a^2b^3.
(1) a^{-3}*b^{-2}=36^{-1} --> a^3b^2=36. Not sufficient.
(2) ab^{-1}=6 --> \frac{b}{a}=\frac{1}{6}. Not sufficient.
(1)+(2) Multiply (1) by (2): a^3b^2*\frac{b}{a}=a^2b^3=36*\frac{1}{6}. Sufficient.
Answer: C.
Note that we are not told that a and b are integers.
a^{-2}*b^{-3}=\frac{1}{a^2b^3}=? So, basically we need to find the value of a^2b^3.
(1) a^{-3}*b^{-2}=36^{-1} --> a^3b^2=36. Not sufficient.
(2) ab^{-1}=6 --> \frac{b}{a}=\frac{1}{6}. Not sufficient.
(1)+(2) Multiply (1) by (2): a^3b^2*\frac{b}{a}=a^2b^3=36*\frac{1}{6}. Sufficient.
Answer: C.
small typo here :
statement 2 says : ab^{-1}=6^{-1} and not ab^{-1}=6 so we have \frac{a}{b} = \frac{1}{6}
so a^2b^3= a^3 *b^2 * \frac{b}{a} = 36 *6 = 216 and not \frac{36}{6}
Hope it helps
Yes, exponent was missing in the second statement. Edited. Thank you.