Question

2 fair dice are thrown. How do you calculate the probability that the event that the sum on the 2 dice is 8?

Answer 1

P(total is 8) = `5/36`

Explanation:

If 2 fair dice are thrown, there are 36 different possible outcomes.
`6xx6 = 36`
We need to know how many of them add up to 8.
A table is usually easiest, but as I don't know how to insert one, let's work through the possibilities..

If the 1st dice lands a 1, we cannot make 8
If the 1st dice lands a 2, the other must be 6.
If the 1st dice lands a 3, the other must be 5.
If the 1st dice lands a 4, the other must be 4.
If the 1st dice lands a 5, the other must be 3.
If the 1st dice lands a 6, the other must be 2.

So out of the 36 possible outcomes, there are only 5 which add up to 8.

P(total is 8) = `5/36`