Is 5 a factor of N?
1) 25 is a factor of 5N
2) 5N is a perfect square
My ans is D. Both in itself are sufficient but the official answer says C.
Is 5 a factor of N?
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- papgust
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Even i'm getting D.
1. 25 is a factor of 5N
25=5*5
If 25 is a factor of 5N, N must have atleast one 5. So, 5 is a factor of N.
Sufficient.
2. 5N is a perfect square.
5N to be a perfect square, N must have atleast one 5. So, 5 is a factor of N.
Sufficient.
1. 25 is a factor of 5N
25=5*5
If 25 is a factor of 5N, N must have atleast one 5. So, 5 is a factor of N.
Sufficient.
2. 5N is a perfect square.
5N to be a perfect square, N must have atleast one 5. So, 5 is a factor of N.
Sufficient.
- linkinpark
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N is not mentioned to be integer so I think there is a trap around that
consider in first statement N = 5*root(10) so 5N = 25*root 10
from second if 5N = perfect square and has 25 as factor, will give N to be a multiple of 5.
consider in first statement N = 5*root(10) so 5N = 25*root 10
from second if 5N = perfect square and has 25 as factor, will give N to be a multiple of 5.
- linkinpark
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I agree that statement 2 is not sufficient by itself but statement 1 is.
According to your explanation if N = 5 root (10) still 5 would be a factor of N
Statement 2 is insufficient because N could be 1/5 5 * 1/5 = 1 which is a perfect sqaure
According to your explanation if N = 5 root (10) still 5 would be a factor of N
Statement 2 is insufficient because N could be 1/5 5 * 1/5 = 1 which is a perfect sqaure
linkinpark wrote:N is not mentioned to be integer so I think there is a trap around that
consider in first statement N = 5*root(10) so 5N = 25*root 10
from second if 5N = perfect square and has 25 as factor, will give N to be a multiple of 5.