Question

A pair of dice are rolled the probability that the sum is 9 given that 5 appeared on the first die is

Answer 1

Answer:

P()=1/36.

because when 5 appear on 1st dice then only (5,4) can make 9

Answer 2

Given,

Pair of dice are rolled

To find,

The probability that the sum is 9 given that 5 appeared on the first die

Solution,

Total number of outcomes when a pair of dice are rolled = 36

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

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

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

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

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

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

Number of cases when the sum is 9 given that 5 appeared on the first die= (5,4)

Probability = favorable cases/ Total number of cases

P( that sum is 9 given that 5 appeared on the first die) = 1/36

Hence, the probability that the sum is 9 given that 5 appeared on the first die is 1/36.