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If a die is rolled twice, what is the probability of rolling a 5 and then a 2?

A)
36
B)
1
3

C)
1
6

D)
2
36

I think it is C but I'm really not sure, could someone tell me if it's right or not?

1 Answer

3 votes
Ok, if you roll the dice once - you'll get:

1, 2, 3, 4, 5 or 6.

If you roll it twice, you can get one of these combinations:

1,1 - 1,2 - 1,3 - 1,4 - 1,5 - 1,6

2,1 - 2,2 - 2,3 - 2,4 - 2,5 - 2,6

3,1 - 3,2 - 3,3 - 3,4 - 3,5 - 3,6

4,1 - 4,2 - 4,3 - 4,4 - 4,5 - 4,6

5,1 - 5,2 - 5,3 - 5,4 - 5,5 - 5,6

6,1 - 6,2 - 6,3 - 6,4 - 6,5 - 6,6

Here there are 36 combinations in total. Your chance of getting a 5 and a 2 is 1/36.

5,2 only appears once in this list of possible combinations. 2,5 doesn't count (as 2 would come up first).
User Chris Trudeau
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