If x+y is an integer, is y an integer?
1) x-y is an integer.
2) x+2y is an integer.
The answer is B. but couldn't find my way out of this maze.
Please give me a way~!!
integer..
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St 1
x - y is Integer
x = 1.5; y = 0.5
x+y = 2 (Int)
x-y = 1 (Int)
But y not Integer. So St1 INSUFF
St 2
x + 2y = (x + y) + y
(Integer + Non Integer) CANNOT add up to an Integer. Since (x + y) is Integer, s y must be an Integer.
SUFF, Hence B
x - y is Integer
x = 1.5; y = 0.5
x+y = 2 (Int)
x-y = 1 (Int)
But y not Integer. So St1 INSUFF
St 2
x + 2y = (x + y) + y
(Integer + Non Integer) CANNOT add up to an Integer. Since (x + y) is Integer, s y must be an Integer.
SUFF, Hence B
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How do you know that X+Y is an integer?sankruth wrote:St 1
x - y is Integer
x = 1.5; y = 0.5
x+y = 2 (Int)
x-y = 1 (Int)
But y not Integer. So St1 INSUFF
St 2
x + 2y = (x + y) + y
(Integer + Non Integer) CANNOT add up to an Integer. Since (x + y) is Integer, s y must be an Integer.
SUFF, Hence B
Using your equation:
(X+Y)+Y: what if X=1.5 and Y=.5, then the answer will end up being an integer...
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- Senior | Next Rank: 100 Posts
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