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Ben rolls four fair 20-sided dice, and each of the dice has faces numbered from 1 to 20. What is the probability that exactly two of the dice show an even number?

Guest Dec 9, 2017
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 #1
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Each die will have the same probabililty of showing an even or odd number

 

So....the probability is

 

C(20,2)  (1/2)^20  =   95 / 524288 ≈ .0181%

 

 

cool cool cool

CPhill  Dec 9, 2017
 #2
avatar+91436 
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Sorry Chris but you read the question incorrectly :(

 

You have found the probability of rolling exactly 2 heads in 20 rolls of the dice but there are only 4 rolls.

 

Continued here:

https://web2.0calc.com/questions/ben-rolls-four-fair-20-sided-dice-and-each-of-the

Melody  Dec 11, 2017

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