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# please help on this problem

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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
+195
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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+0 Answers

#1
+195
+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