Chapter 13.6, Problem 2ACYP

To determine

To determine probability of given event.

Answer to Problem 2ACYP

Probability of getting double or sum of 9 is $\frac{15}{54}$ or 27.7%

Explanation of Solution

Given information :

Two dice are rolled.

Total possible outcome while rolling 2 dice are $6\times 6=36$

Possibilities of doubles on the two dice are,

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

Hence the probability is $\frac{6}{36}=\frac{1}{6}$

Possibilities of getting a sum of 9 are,

(3,6), (4,5), (5,4), (6,3)

Hence the probability of getting sum of 9 is $\frac{4}{36}=\frac{1}{9}$

Hence probability of getting double or sum of 9 is $\frac{1}{6}+\frac{1}{9}=\frac{15}{54}$ or 27.7%