It is currently 26 Jun 2017, 05:27

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

M05 P.S Problem

Author Message
Manager
Joined: 02 Oct 2008
Posts: 58

Show Tags

10 Dec 2009, 21:29
If a fair coin marked 1 and 2, and a fair die are rolled together, what is a probability to have the sum even?
Ans is 1/2

Possible combination for the above question is
1+1,1+3,1+5,2+2,2+4,2+6,6+2,4+2,5+1,3+1

Probability = 10/12 = 5/6

Why is 2+6 and 6+2 etc. are considered as same in the above problem?
VP
Joined: 05 Mar 2008
Posts: 1469

Show Tags

10 Dec 2009, 21:41
tania wrote:
If a fair coin marked 1 and 2, and a fair die are rolled together, what is a probability to have the sum even?
Ans is 1/2

Possible combination for the above question is
1+1,1+3,1+5,2+2,2+4,2+6,6+2,4+2,5+1,3+1

Probability = 10/12 = 5/6

Why is 2+6 and 6+2 etc. are considered as same in the above problem?

because the six can only come out on the die and the 2 on the fair coin...therefore, 6 has to be the die whether you roll the die first or second
Re: M05 P.S Problem   [#permalink] 10 Dec 2009, 21:41
Similar topics Replies Last post
Similar
Topics:
3 M05 #16 15 19 Dec 2012, 16:21
6 M05 #4 21 20 Nov 2012, 18:32
26 m05 #22 28 18 Jul 2014, 09:16
3 ps - wheels (m05q23) 23 13 Sep 2012, 20:46
7 PS - Movies (m05q27) 26 24 Jul 2014, 14:01
Display posts from previous: Sort by

M05 P.S Problem

Moderator: Bunuel

 Powered by phpBB © phpBB Group and phpBB SEO Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.