Positive even integers and prime numbers

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Positive even integers and prime numbers

by lavinia » Thu Dec 02, 2010 9:24 am
For every positive even integer n, the function f(n) is defined to the product of all even integers from 2 to n, inclusive. If p is the smallest prime factor of f(100)+1, then p is:
(A) between 2 and 10
(B) between 10 and 20
(C) between 20 and 30
(D) between 30 and 40
(E) greater than 40

Answer: [spoiler](E)[/spoiler]

How do you solve this kind of problem?

Thanks!
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by goyalsau » Thu Dec 02, 2010 9:28 am
lavinia wrote:For every positive even integer n, the function f(n) is defined to the product of all even integers from 2 to n, inclusive. If p is the smallest prime factor of f(100)+1, then p is:
(A) between 2 and 10
(B) between 10 and 20
(C) between 20 and 30
(D) between 30 and 40
(E) greater than 40

Answer: [spoiler](E)[/spoiler]

How do you solve this kind of problem?

Thanks!
This problem has been discussed many times on this forum ,
I would recommend you to do some search on the forum because posting the problem.
Saurabh Goyal
[email protected]
-------------------------


EveryBody Wants to Win But Nobody wants to prepare for Win.

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by lavinia » Thu Dec 02, 2010 9:51 am
Hi Goyalsau,

I've searched this problem, but I couldn't find it. If you have the exactly post, I really appreciate your help.

Thanks!


goyalsau wrote:
lavinia wrote:For every positive even integer n, the function f(n) is defined to the product of all even integers from 2 to n, inclusive. If p is the smallest prime factor of f(100)+1, then p is:
(A) between 2 and 10
(B) between 10 and 20
(C) between 20 and 30
(D) between 30 and 40
(E) greater than 40

Answer: [spoiler](E)[/spoiler]

How do you solve this kind of problem?

Thanks!
This problem has been discussed many times on this forum ,
I would recommend you to do some search on the forum because posting the problem.

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by justvishu4 » Thu Dec 02, 2010 11:34 am
lavinia wrote:Hi Goyalsau,

I've searched this problem, but I couldn't find it. If you have the exactly post, I really appreciate your help.

Thanks!


goyalsau wrote:
lavinia wrote:For every positive even integer n, the function f(n) is defined to the product of all even integers from 2 to n, inclusive. If p is the smallest prime factor of f(100)+1, then p is:
(A) between 2 and 10
(B) between 10 and 20
(C) between 20 and 30
(D) between 30 and 40
(E) greater than 40

Answer: [spoiler](E)[/spoiler]

How do you solve this kind of problem?

Thanks!
This problem has been discussed many times on this forum ,
I would recommend you to do some search on the forum because posting the problem.
I just found them in a quick search-

https://www.beatthegmat.com/tough-prime- ... 25475.html

https://www.manhattangmat.com/forums/for ... t1152.html

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by goyalsau » Thu Dec 02, 2010 7:31 pm
justvishu4 wrote: This problem has been discussed many times on this forum ,
I would recommend you to do some search on the forum because posting the problem.
[/quote]

I just found them in a quick search-

https://www.beatthegmat.com/tough-prime- ... 25475.html

https://www.manhattangmat.com/forums/for ... t1152.html[/quote]


Thanks Buddy, You did the work of my part.
Saurabh Goyal
[email protected]
-------------------------


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by lavinia » Sat Dec 04, 2010 10:51 am
Thanks a lot justvishu4 and goyalsau. You've made my day :)
goyalsau wrote:
justvishu4 wrote: This problem has been discussed many times on this forum ,
I would recommend you to do some search on the forum because posting the problem.
I just found them in a quick search-

https://www.beatthegmat.com/tough-prime- ... 25475.html

https://www.manhattangmat.com/forums/for ... t1152.html[/quote]


Thanks Buddy, You did the work of my part.[/quote]