Is the integer n a multiple of 15?
(1) n is a multilple of 20
(2) n+6 is a multiple of 3
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codesnooker
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Answer is (C)
Condition 1: n is multiple of 20 (not sufficient, lets say n = 20, which is not multiple of 15)
Condition 2: n + 6 is multiple of 3 (not sufficient, lets say n = 3, which is not multiple of 15)
Let try both conditions together:
From condition n could be 20, 40, 60, 80, 100, 120......
On applying condition 2 on the above dataset, our dataset would be reduced
to 60, 120, 180......
which is divisible by 15.
Hence both conditions together are sufficient. (C)
Condition 1: n is multiple of 20 (not sufficient, lets say n = 20, which is not multiple of 15)
Condition 2: n + 6 is multiple of 3 (not sufficient, lets say n = 3, which is not multiple of 15)
Let try both conditions together:
From condition n could be 20, 40, 60, 80, 100, 120......
On applying condition 2 on the above dataset, our dataset would be reduced
to 60, 120, 180......
which is divisible by 15.
Hence both conditions together are sufficient. (C)
