Question

A pair of six-sided dice is rolled one time. What is the probability that the number 5 will appear?

Answer 1

Given that there is a pair of six-sided dice, let be the probability to obtain a 5 in the first dice:

`P_1`

And let be the probability to obtain a 5 in the second dice:

`P_2`

Then, the probability to obtain a 5 in one of the two dices will be equal to:

`P=P_1\cup P_2`

Therefore:

`P=P_1+P_2`

The dice has 6 sides, hence the probability that a 5 appears for each dice is:

`(1)/(6)`

Therefore:

`P=(1)/(6)+(1)/(6)`

Adding the fractions, you get:

`\begin{gathered} P=(2)/(6) \\ \\ P=(1)/(3) \end{gathered}`

Hence, the answer is:

`P=(1)/(3)`