Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 19 Apr 2015, 01:30

### 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

# you got 1 min..go! Let b be a positive integer and a =

Author Message
TAGS:
CEO
Joined: 15 Aug 2003
Posts: 3469
Followers: 61

Kudos [?]: 701 [0], given: 781

you got 1 min..go! Let b be a positive integer and a = [#permalink]  14 Sep 2003, 03:54
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
you got 1 min..go!

Let b be a positive integer and a = b^2 тАУ b. If b ≥ 4, then a^2 тАУ 2a
is divisible by:

a) 15
b) 20
c) 24
d) None of these
Manager
Joined: 26 Dec 2003
Posts: 227
Location: India
Followers: 1

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

Got 24 too but spent nearly 2 min, praet and anand is there any short cut to do that in less than 1 min
Intern
Joined: 01 Dec 2003
Posts: 35
Location: infront of my LCD
Followers: 0

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

a^2 тАУ 2a = a(a-2) = (b^2 - b)(b^2 - b - 2) = b(b-1)(b+1)(b-2)

so if b=4, then a^2 -2a = 4*3*5*2

I get all of them.
Director
Joined: 28 Oct 2003
Posts: 503
Location: 55405
Followers: 1

Kudos [?]: 10 [0], given: 0

24, indeed. Nice trick making the other choices work for 4 and 5.
Similar topics Replies Last post
Similar
Topics:
25 If a, b, and c are positive integers such that 1/a + 1/b = 1 15 18 Nov 2012, 12:06
Let p be the product of the positive integers between 1 and 1 10 May 2012, 05:14
20 If a and b are both positive integers, is b^(a+1) - ba^b 13 09 Aug 2011, 04:20
3 If a and b are both positive integers, is b^(a + 1)– b*(a^b) 3 10 Jul 2011, 05:42
Let a, b, c, d, e, f, g, h, I be positive integers from 1 to 1 27 Oct 2005, 18:23
Display posts from previous: Sort by