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Four slips of paper labeled A, B, C and D are drawn from a hat at random, one at a time, without replacement. What is the probability of drawing C first and D last? Express your answer as a common fraction.

 Jun 9, 2019

Best Answer 

 #1
avatar+99 
+1

There are 4!=24 ways to draw the slips out of the hat.

 

There are only 2 ways to draw C first and D last:

CABD

CBAD

because once you decide when you draw C and D, the only two papers you have to worry about ordering are A and B in the middle and there are only 2 ways to do that.

So the probability is \(\frac{2}{24}=\boxed{\frac{1}{12}}\)

.
 Jun 9, 2019
 #1
avatar+99 
+1
Best Answer

There are 4!=24 ways to draw the slips out of the hat.

 

There are only 2 ways to draw C first and D last:

CABD

CBAD

because once you decide when you draw C and D, the only two papers you have to worry about ordering are A and B in the middle and there are only 2 ways to do that.

So the probability is \(\frac{2}{24}=\boxed{\frac{1}{12}}\)

power27 Jun 9, 2019

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