If Enid and Topanga each roll a single ten-sided die (which has sides numbered 1 through 10), what is the probability that Enid will roll a larger number than Topanga does?
A. 2/5
B. 9/20
C. 49/100
D. 99/200
E. 1/2
OA B
Source: Veritas Prep
Solve 700-Level Algebra Qs In 90 Secs!
Master 700-level Inequalities and Absolute Value Questions
Attend this free GMAT Algebra Webinar and learn how to master the most challenging Inequalities and Absolute Value problems with ease.
If Enid and Topanga each roll a single ten-sided die (which has sides numbered 1 through 10), what is the probability
This topic has expert replies
-
- Moderator
- Posts: 7187
- Joined: Thu Sep 07, 2017 4:43 pm
- Followed by:23 members
Timer
00:00
Your Answer
A
B
C
D
E
Global Stats
-
- Master | Next Rank: 500 Posts
- Posts: 415
- Joined: Thu Oct 15, 2009 11:52 am
- Thanked: 27 times
Don't forget ties.
The odds of a tie are one rolls a number and the other has 1/10 chance of matching, so
1/10 chance of tie
This leaves 9/10 chance to roll different numbers.
Half the time a given person will roll higher than the other, so
1/2*9/10 = [spoiler]9/20, B[/spoiler]
The odds of a tie are one rolls a number and the other has 1/10 chance of matching, so
1/10 chance of tie
This leaves 9/10 chance to roll different numbers.
Half the time a given person will roll higher than the other, so
1/2*9/10 = [spoiler]9/20, B[/spoiler]