Question

A number cube with sides labeled 1 through 6 is rolled two times, and the sum of the numbers that end face up is calculated. What is the probability that the sum of the numbers is 3?

Answer 1

First, how many things could happen? Second how many ways could we make 3 with two dice?

Answer 2

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

Answer 3

Now count possible rolls (denominator) and desirable (roll=3) (numerator) to get a fractional probability.

Answer 4

1/18 ?

Answer 5

@mrbarry

Answer 6

Correct (2/36)

Answer 7

Thank you ♥