If Enid and Topanga each roll a single tensided 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
If Enid and Topanga each roll a single tensided die (which has sides numbered 1 through 10), what is the probability
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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]