Probability

 

What is the probability that at least two of the faces match when you roll four fair six-sided dice? Express your answer as a common fraction.  

 

There's a 1/1 chance that the first die will be any number 

There's a 1/6 chance that the second die will be the same number 

There's a 1/6 chance that the third     die will be the same number  

There's a 1/6 chance that the fourth  die will be the same number  

 

So the probability is 1/1 • 1/6 • 1/6 • 1/6  =  1/216  

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