Question

When rolling two dice, what is the probability that the sum is 7 given that one die is a 5?

Answer 1

If one die is 5, there's only one possible result on the other die to get 7.

What is the probability of rolling what you need?

Answer 2

There are 6 x 6 or 36 options, all are equally likely, 7 occurs 6 times, so the chances are 6/36 or 1/6. hope this helps?

Answer 3

I don't get it. What do you mean by 7 occurs 6 times?

Answer 4

to get a 7:
dice1 dice2
1 6
2 5
3 4
4 3
5 2
6 1

six different ways..
now how many of those have a 5 showing?

Answer 5

if you know that one die is a 5 then your sample space has only 6 elements in it
of those six elements, exactly one gives a total of 7, namely (5,2)

Answer 6

therefore your answer is \(\frac{1}{6}\)

Answer 7

there are 11 outcomes when one of the outcome is 5.

Answer 8

@dpaInc is conditioning the other way
that is, showing how to compute the probability that one die shows 5 given the total is 7

Answer 9

yep ur right... my bad....

Answer 10

(1,5), (2, 5), (3,5), (4,5), (5,5), (5,6), (5,1), (5,2), (5,3), (5,4), (6,5)

Answer 11

there are only of those 11 outcomes that have a sum 7. so the probability is 2/11

Answer 12

there are only 2 of those 11 outcomes that have a sum 7. so the probability is 2/11

Answer 13

You guys are so helpful, thank you!

Answer 14

thanks for the medal, @DarkendSinz30

Answer 15

You're welcome.