Question

If you are playing a game that has a pair of dice you have to roll, what is the

probability that the sum of the numbers you roll will be a 9?

Probabilities are stated as fractions. For instance, the probability that you will get
heads on a coin flip are "1 out of 2" or 1/2. State your answer as a fraction in
simplest form.

Answer 1

1/9

Explanation:

For each of the first die's 6 outcomes, the second die also has a possible 6 outcomes.

6 × 6 = 36

There are 36 different outcomes from

1, 1

1, 2

1, 3

...
6, 6

Many outcomes have the same sum. For example, 3, 4 and 4, 3 both add to 7.

How many outcomes add to 9?

3, 6

4, 5

5, 4

6, 3

4 different outcomes out of a possible 36 different outcomes add to 9.

p(sum of 9) = 4/36 = 1/9