[Prep][DS][My mistakes] HSPA posts

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[Prep][DS][My mistakes] HSPA posts

by HSPA » Sun Nov 13, 2011 5:03 am
If r and s are positive integers, is r/s an integer?

1. Every factor of s is also a factor of r
2. Every prime factor of s is also a factor of r

Hi Mitch,
In the above question's option A is r = s in value?
First take: 640 (50M, 27V) - RC needs 300% improvement
Second take: coming soon..
Regards,
HSPA.
Source: — Data Sufficiency |

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by rijul007 » Sun Nov 13, 2011 5:44 am
In the above question's option A is r = s in value?
In A,
r = p*s

where p is an Integer..[/quote]

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by rijul007 » Sun Nov 13, 2011 5:46 am
IMO: A

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by winniethepooh » Sun Nov 13, 2011 5:49 am
IMO:D

I don't think r needs to be equal to s.

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by neelgandham » Sun Nov 13, 2011 6:44 am
IMO A


If r and s are positive integers, is r/s an integer?
1. Every factor of s is also a factor of r
If every factor of s is also a factor of r then r = k * s, where k is an Integer and r/s= k, an Integer. Hence, Sufficient !
2. Every prime factor of s is also a factor of r
e.g.1 s = 2, r = 4 prime factor = 2, r/s is an Integer
e.g.2 s = 8, r = 4 prime factor = 2, r/s is not an Integer

Hence Insufficient!
Anil Gandham
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by vaibhavgupta » Sun Nov 13, 2011 7:18 am
HSPA wrote:If r and s are positive integers, is r/s an integer?

1. Every factor of s is also a factor of r
2. Every prime factor of s is also a factor of r
+1 for A!

Needed some thought into it! :)
If OA is A, IMO B
If OA is B, IMO C
If OA is C, IMO D
If OA is D, IMO E
If OA is E, IMO A

FML!! :/