If x and y are integers, and x/y is not an integer then which of the following must be true?
A. x is odd and y is even.
B. x is odd and y is odd.
C. x is even and y is odd.
D. x<y
E. None of the above
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DS: Difficulty level: 700, Source: Economist
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The key word here is mustaishwaryav12 wrote:If x and y are integers, and x/y is not an integer then which of the following must be true?
A. x is odd and y is even.
B. x is odd and y is odd.
C. x is even and y is odd.
D. x<y
E. None of the above
So, if we can find a case in which an answer choice is NOT true, then we can eliminate that answer choice.
A. x is odd and y is even.
x = 3 and y = 11 satisfies the condition that x/y is not an integer
Since y is NOT even, we can ELIMINATE A
B. x is odd and y is odd.
x = 4 and y = 6 satisfies the condition that x/y is not an integer
Since x is NOT odd, we can ELIMINATE B
C. x is even and y is odd.
x = 5 and y = 6 satisfies the condition that x/y is not an integer
Since x is NOT even, we can ELIMINATE C
D. x < y
x = 5 and y = 2 satisfies the condition that x/y is not an integer
Since x > y, we can ELIMINATE D
Answer: E
Cheers,
Brent
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I randomly assigned values to x and y (5/3, 3/5, 5/4 , 6/4 ) and checked the options. Options A, B, C and D. Hence E.aishwaryav12 wrote:If x and y are integers, and x/y is not an integer then which of the following must be true?
A. x is odd and y is even.
B. x is odd and y is odd.
C. x is even and y is odd.
D. x<y
E. None of the above
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