Is X divisible by 15

Question

Is X divisible by 15?

1. When X is divided by 10, the result is an integer
 2.  X^2  is a multiple of 30

* Statement (1) ALONE is sufficient, but Statement (2) ALONE is not sufficient
 * Statement (2) ALONE is sufficient, but Statement (1) ALONE is not sufficient
 * BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient
 * EACH statement ALONE is sufficient
 * Statements (1) and (2) TOGETHER are NOT sufficient

x2suresh · Answer

1.

when X=10.. Is X divisible by 15? No
when X=30 .. is X divisible by 15? Yes
not sufficient

2. X^2 =30k

assume X = sqrt(30) (x can be fractional number) Is X divisible by 15? No
ASSUM X= 30 is X is divisble by 15? Yes
not sufficient

combined

combined
from statement1 it is clear that X must be integer.
 X^2 =30k
 For X to be integer K must be multiple of 30*l^2 (here l any integer number.1,2.. ..etc)

X --> multiple of 30

Is X divisible by 15> Yes.

sufficient

C

unplugged · Answer

Agree with C

Cheers,
Unplugged

sondenso · Answer

B.

X^2 is a multiple of 30, X must be a multiple of 30 or X must contain 30, so X must be divisible by 15.

chicagocubsrule · Answer

If x^2 is a multiple of 30, then x must contain at least a: 2, 3, 5 making B the correct choice. What's the OA?

x2suresh · Answer

X^2 =30k
  assume X = sqrt(30) i.e X^2=30   (x can be fractional number) Is X divisible by 15? No
ASSUM X= 30 is X is divisble by 15? Yes
not sufficient

sondenso · Answer

Agree, X is NOT an integer! silly mistake! :-D

xALIx · Answer

Great stuff, OA is C

Ibodullo · Answer

Tricky question

Is X divisible by 15

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