If n is not an integer, is 5n an integer?
(1) 3n + 2 is an integer divisible by 10.
(2) 6n - 1 is an integer divisible by 5.
Made Up!
is 5n an integer?
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Question : Is 5n an Integer?If n is not an integer, is 5n an integer?
(1) 3n + 2 is an integer divisible by 10.
(2) 6n - 1 is an integer divisible by 5
Statement 1) 3n+2 is an integer divisible by 10
i.e. 3n + 2 is a Multiple of 10
therefore possible values of (3n + 2) = 10, 20, 30, 40, 50, .... and so on
Therefore values of n = 8/3, 18/3, 28/3 .....and so on respectively
For each value of n obtained above, 5n is never an Integer. Consistent solution therefore SUFFICIENT
Statement 2) 6n-1 is an integer divisible by 5
i.e. 6n - 1 is a Multiple of 5
therefore possible values of (6n - 1) = 5, 10, 15, 20, 25 .... and so on
Therefore values of n = 1 (not acceptable being integer), 11/6, 8/3, 7/2, 13/3 .....and so on respectively
for n = 11/6, 5n is NOT an Integer
for n = 8/3, 5n is NOT an Integer and so on
For each value of n obtained above, 5n is never an Integer. Consistent solution therefore SUFFICIENT
Answer : Option D
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