What is the value of (x^2a)*(y^3b)?
(1) xy=1
(2) a=b=3
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jjk
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E
Statement 1 -- INSUFFICIENT
Although xy = 1, we do not know whether x and y are integers nor whether they are positive. x could be .25 and y could be 4, giving us varied answers. x could also be -.25 and y could be -4. If y is -4 and raised to an odd exponent, the value of x^2b * y^3b will definitely not be 1.
Statement 2 -- INSUFFICIENT
We know nothing about the base values (x and y).
Combined -- INSUFFICIENT
We could end up with any of the following possibilities:
1^6 * 1^9
.5^6 * 2^9
.25^6 * 4^9
Answer is E.
Statement 1 -- INSUFFICIENT
Although xy = 1, we do not know whether x and y are integers nor whether they are positive. x could be .25 and y could be 4, giving us varied answers. x could also be -.25 and y could be -4. If y is -4 and raised to an odd exponent, the value of x^2b * y^3b will definitely not be 1.
Statement 2 -- INSUFFICIENT
We know nothing about the base values (x and y).
Combined -- INSUFFICIENT
We could end up with any of the following possibilities:
1^6 * 1^9
.5^6 * 2^9
.25^6 * 4^9
Answer is E.
xy = 1 either x=y = 1 or -1 or x,y are reciprocals, no idea about a,b...insuffern5231 wrote:What is the value of (x^2a)*(y^3b)?
(1) xy=1
(2) a=b=3
from2
x,y not known..insuff
both
x^6 * y^9 = (xy)^6 * y^3 = 1*y^3..insuff
E
