What is the value of (x - y)^4?
(1)The product of x and y is 7.
(2)x and y are integers.
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
Can anyone help solving this ... (x-y)^4
This topic has expert replies
Has to be (C).
Statement I only tells you that XY = 7, but doesn't tell you that X and Y are integers as such X = 49 and Y = 1/7, X = 1/3 Y = 21 etc..
Statement II only tells you that X and Y are integers, not suff...
Both together tell you that X and Y are either 1, 7 or 7,1 or -1, -7 or -7, -1. In all cases x-y will give you 6 or -6, raised to the fourth give you the same answer...
Statement I only tells you that XY = 7, but doesn't tell you that X and Y are integers as such X = 49 and Y = 1/7, X = 1/3 Y = 21 etc..
Statement II only tells you that X and Y are integers, not suff...
Both together tell you that X and Y are either 1, 7 or 7,1 or -1, -7 or -7, -1. In all cases x-y will give you 6 or -6, raised to the fourth give you the same answer...
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Answer should be C
Statement 1 - x = 7, y = 1, or x = -7, y = -1, or x = 49, y = 1/7 satisfy the statement
Statement 2 - this tells us nothing but x and y are integers, they could be any integer
combining the statements - we get x = 7, y = 1 and x = -7, y = -1, but (x - y)^4 will have the same value irrespective of sign of x and y.
Statement 1 - x = 7, y = 1, or x = -7, y = -1, or x = 49, y = 1/7 satisfy the statement
Statement 2 - this tells us nothing but x and y are integers, they could be any integer
combining the statements - we get x = 7, y = 1 and x = -7, y = -1, but (x - y)^4 will have the same value irrespective of sign of x and y.
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but s1) never tells that x and y are int it can be 7/5*5 ; 7/2*2 ;7/3*3 and so onapuso wrote:(A)
since 7 is a prime number thus if x*y has to be 7 then its either x and y are 1 & 7 or -1 & -7...but in either of the cases the value of (x - y)^4 can be derived and would be the same.
whats the OA.
it has to be C
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