GMATPrep: Product of even integers from 2 to n

agoyal2

Did not get how to approach this one:

Q> For every positive integer n, the function h(n) is defined to be the product of all the even integers from 2 to n, inclusive. If p is the smallest prime factor of h(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

Correct answer: E

II · Posted: Sat Aug 30, 2008 7:11 am Post subject:

Hi Agoyal ... I see that this is your first post ... welcome to the forum !
This question has already been posted before ... see the following link:
http://www.beatthegmat.com/gmat-prep-number-properties-t8649.html?highlight=100

Just a suggestion: its probably worth doing a quick search by inputting the some of text of the question as the search criteria to see if it already has been posted. Most of the GMATPrep questions will have been posted on here already.

vaivish · Posted: Sat Aug 30, 2008 7:12 am Post subject:

here when u have n=100 u must work backwards. eg. say for 100 the prime divider is 2. Then go to 98, its prime divider is 7, 82 its prime divider is 41....hence ans is E......u definately have higher numbers than 41 like 43(86). BAckward working is the key...

sudhir3127