Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

 It is currently 22 May 2017, 12:51

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# If an integer n is to be chosen at random from the integers

Author Message
Senior Manager
Joined: 02 Dec 2007
Posts: 450
Followers: 3

Kudos [?]: 222 [0], given: 6

If an integer n is to be chosen at random from the integers [#permalink]

### Show Tags

19 Sep 2008, 10:30
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

If an integer n is to be chosen at random from the integers 1 to 96, inclusive, what is the probability that n(n + 1)(n + 2) will be divisible by 8?

A.1/4
B.3/8
C.1/2
D.5/8
E.3/4

Last edited by Nihit on 19 Sep 2008, 10:53, edited 1 time in total.
Intern
Joined: 02 Sep 2008
Posts: 45
Followers: 0

Kudos [?]: 0 [0], given: 0

### Show Tags

19 Sep 2008, 10:50
Buddy,

I think you forget to write answers in options A, B, C, D and E.

By the way, I come up with anser 1/2.
Intern
Joined: 02 Sep 2008
Posts: 45
Followers: 0

Kudos [?]: 0 [0], given: 0

### Show Tags

19 Sep 2008, 10:56
Sorry..

It is 5/8. I miss some number..
Senior Manager
Joined: 02 Dec 2007
Posts: 450
Followers: 3

Kudos [?]: 222 [0], given: 6

### Show Tags

19 Sep 2008, 10:57
thanks mate, yeah E is the answer , am somehow getting 1/2 as well. Can u explain ?
Manager
Joined: 21 Aug 2008
Posts: 204
Followers: 1

Kudos [?]: 14 [0], given: 0

### Show Tags

19 Sep 2008, 11:35
I'm sure I'd get it wrong in real q though I'd think it is a bit suspicious to have a simple 1/2.

It's 5/8, or 60/96. From the net and simple calculation, we could get easy 48. However, we must notice that there are more numbers that are divisible by 8 under the term of (n)(n+1)(n+2). We have 12 more. For instance, 14x15x16, 15x16x17, 16x17x18...all three can be divided by 8.
Intern
Joined: 15 Aug 2008
Posts: 17
Followers: 0

Kudos [?]: 0 [0], given: 0

### Show Tags

19 Sep 2008, 14:15
probably would get this wrong in exam but..
all even numbers : n(n+1)(n+2) seem to be divisible by 8.(48 in all)
all odd numbers, every odd number that is followed by a multiple of 8 will be divisble by 8, so we have 7,15,23,31,39,47,55,63,71,79,87,95. (12 in all)
so probability = (48 + 12) / 96 = 60/96 = 5/8
Current Student
Joined: 28 Dec 2004
Posts: 3364
Location: New York City
Schools: Wharton'11 HBS'12
Followers: 15

Kudos [?]: 297 [0], given: 2

### Show Tags

19 Sep 2008, 15:32
i get 5/8..

its like this..we know that every 1 number in 8 numbers will be divisible by 8...right.

so if n=8 then the whole equation is divisible by 8..if (n+1) is 8 then the same thing and so on..

so basically in 8 numbers we know 3 numbers will make the whole stem divisible by 8..

but now lets see there are 2 such numbers that are not in the 8--16 range that would make the stem divisible they are when n=2 or n=4

so total numbers is 5/8
SVP
Joined: 05 Jul 2006
Posts: 1747
Followers: 6

Kudos [?]: 357 [0], given: 49

### Show Tags

19 Sep 2008, 15:56
Nihit wrote:
If an integer n is to be chosen at random from the integers 1 to 96, inclusive, what is the probability that n(n + 1)(n + 2) will be divisible by 8?

A.1/4
B.3/8
C.1/2
D.5/8
E.3/4

3 consecutive integers are devesible by 8 , if one is a multiple of 4 and anothoer is a multiple of 2 , or one of them is a multiple of 8 . i think this is the key ..
Re: integer n   [#permalink] 19 Sep 2008, 15:56
Display posts from previous: Sort by