Question

Find the probability of rolling a sum of nine with a single toss of two fair six-sided dice.
Answer

1/9

1/18

1/36

1/4

Answer 1

The sample space has 36 possible combinations of numbers. These can be set out in column form as follows:
6,6 5,6 4,6 3,6 2,6 1,6
6,5 5,5 4,5 3,5 2,5 1,5
6,4 5,4 4,4 3,4 2,4 1,4
6,3 5,3 4,3 3,3 2,3 1,3
6,2 5,2 4,2 3,2 2,2 1,2
6,1 5,1 4,1 3,1 2,1 1,1
Count up the number of outcomes that sum to nine and divide by 36 to find the answer.

Answer 2

is their another way?

Answer 3

What is hard about counting the number of outcomes that give a sum of six?

Answer 4

look, i dont have time for this!

Answer 5

The method that I have presented is the easiest way to understand how to solve this question.