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xALIx
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Is X divisible by 15 01 Feb 2009, 13:41
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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



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x2suresh
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Is X divisible by 15 01 Feb 2009, 14:05
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x-ALI-x
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
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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
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Is X divisible by 15 01 Feb 2009, 23:58
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Agree with C

Cheers,
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Is X divisible by 15 02 Feb 2009, 00:27
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x-ALI-x
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
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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.
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Is X divisible by 15 02 Feb 2009, 00:59
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x-ALI-x
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

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.
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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?
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Is X divisible by 15 02 Feb 2009, 01:02
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x-ALI-x
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

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.

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?
Show more

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
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Is X divisible by 15 02 Feb 2009, 01:13
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x2suresh
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
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Agree, X is NOT an integer!

silly mistake! :-D :-D
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Is X divisible by 15 02 Feb 2009, 17:46
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Great stuff, OA is C
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Ibodullo
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Is X divisible by 15 02 Feb 2009, 21:44
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Tricky question :)



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