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gmattesttaker2
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Hello,
This is from MGMAT:
If a and b are positive integers such that a < b, is b even?
(1) b/2 - a/2 is an integer.
(2) 3b/4 - a/2 is an integer.
OA: B
I was trying to solve this as follows:
1) b/2 - a/2 = integer
(b - a)/2 = integer
b - a = even integer
So, b = a = odd
or b = a = even
Insuff.
2) 3b/4 - a/2 = integer
3b/4 - 2a/4 = integer
3b - 2a = even integer
3b - even integer = even integer
However, I was stuck after this point since 3b is odd.
Can you please assist? Thanks a lot
Sorry: Posted it in wrong section. Moved it to DS
This is from MGMAT:
If a and b are positive integers such that a < b, is b even?
(1) b/2 - a/2 is an integer.
(2) 3b/4 - a/2 is an integer.
OA: B
I was trying to solve this as follows:
1) b/2 - a/2 = integer
(b - a)/2 = integer
b - a = even integer
So, b = a = odd
or b = a = even
Insuff.
2) 3b/4 - a/2 = integer
3b/4 - 2a/4 = integer
3b - 2a = even integer
3b - even integer = even integer
However, I was stuck after this point since 3b is odd.
Can you please assist? Thanks a lot
Sorry: Posted it in wrong section. Moved it to DS
