If x + y is an integer, is y an integer?
(1) x - y is an integer.
(2) x + 2y is an integer.
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integers
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nervesofsteel
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nervesofsteel
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realized my mistakenervesofsteel wrote:If x + y is an integer, is y an integer?
(1) x - y is an integer.
(2) x + 2y is an integer.
OA B
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kstv
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(2)x+2y = x+y+ynervesofsteel wrote:If x + y is an integer, is y an integer?
(1) x - y is an integer.
(2) x + 2y is an integer.
x+y and x+y+y are integers
possible only if y is an integer
(3) x=3/2 y = 1/2.
x+y = 2 x-y = 1
but y is not an integer.
picking fractions for x and y will be easier to disprove.
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akhpad
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Statement 1:nervesofsteel wrote:If x + y is an integer, is y an integer?
(1) x - y is an integer.
(2) x + 2y is an integer.
x + y = m, x - y = n
y = (m - n) / 2
y may or may not be integer
Insufficient
Statement 2:
x + y = m, x + 2y = n
y = n - m
y must be integer
Sufficient
Ans B
