Is x divisible by 9?

Question

(1) x is divisible by 3.
(2) When x is divided by 6, the remainder is 3.

Skywalker18 · Answer

Is x divisible by 9 =3^2
that x should have at least 2 factors of 3
(1) x is divisible by 3.
If x= 3 or 6 , then it won't be divisible by 9
If x= 9 or 18 , then it would be divisible by 9
Not sufficient.
(2) When x is divided by 6, the remainder is 3
x= 6n + 3
where n is quotient
If x= 3 , it is not divisible by 9 .
If x=9 , it is divisible by 9.
Not sufficient.
Combining 1 and 2 , 
If x= 3 , it is not divisible by 9 .
If x=9 , it is divisible by 9.
Not sufficient.

Answer E

stonecold · Answer

Nice Question
Here we can see that x=3 and x=9 is satisfied by both the statements 
hence E

amanvermagmat · Answer

(1) A multiple of 3 may or may not be a multiple of 9 (eg, 27 is but 24 is not), so this statement is Insufficient.

(2) x is of the form '6k + 3', where k is a non-negative integer. If we put k=1, we get 9 which is a multiple of 9. But if we put k=2, we get 15 which is not a multiple of 9. So this statement is Insufficient.

Combining the two, a number of the form '6k + 3' is anyway a multiple of 3, and from statement 2 we have seen that this information is not sufficient to know whether the number is divisible by 9 or not. Hence  E answer

Is x divisible by 9?

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