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if a single six sided dice is rolled twice what is the probability the sum is greater than 5 if the first roll was a 3

User Chicky
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2 Answers

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34% because every time you roll the dice each side has a probability of 17%, so since there are numbers 5 and 6 you want to roll, there is a 34% you will get those numbers. the first roll doesn't have an affect on your next roll

User Sari Alalem
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1 vote
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 Hauns TM
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