Number properties problem - No picking numbers strategy

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How can i solve this problem without the picking numbers strategy:

If "p" is a positive integer, what is the value of "p"?

1) p/4 is a prime number

2) p is divisible by 3
Alberto

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by cramya » Sun Dec 14, 2008 6:18 pm
Not sure why picking numbers is bad here.

here it goes

Stmt I

p/4 = prime so p = 4 * prime

There are several primes so p could be anything

INSUFF

Stmt II

p is divisible by 3

there are many multiples of 3 so p cpuld be any postive multiple of 3

INSUFF

Stmt I and II together

p = 4*prime

p divisible by 3

i.e 4 * primenumber divisible by 3

4 is not divisisble by 3 so the prime number must be divisible by 3. This prime number has to be 3 and p=12 since by definition of prime number only that number and 1 can be its factors.

One defnite answer

Choose C)

Whats the OA(OFFICIAL ANSWER)?

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by cramya » Sun Dec 14, 2008 6:21 pm
CIAO,
If possible please post OA'S using spoiler when posting questions.

Eg: OA: whatever the oa is

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by vishubn » Sun Dec 14, 2008 6:33 pm
Indeed ! one more vote for C

vishu
KILL !! DIE !! or BEAT my FEAR !!! de@D END!!

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by vishubn » Sun Dec 14, 2008 6:34 pm
Cramya !

I dont like the number 99 ( thanked 99 times...... )


thank you for all the help so far on this forum

Vishu
KILL !! DIE !! or BEAT my FEAR !!! de@D END!!

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by cramya » Sun Dec 14, 2008 6:41 pm
Vishu,

:-) Good luck my friend!

Regards,
Cramya

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by srisl11 » Sun Dec 14, 2008 6:59 pm
vishubn wrote:Cramya !

I dont like the number 99 ( thanked 99 times...... )


thank you for all the help so far on this forum

Vishu
Cramya ..deserves more than that :)

Thank you Cramya