Question

Calculate the probability of winning: Roll two standard dice. You win if you get a sum of 4 or get a sum of 8. Round answer to one decimal place, for example if your answer is 0.65 enter 0.7

Answer 1

The possible outcomes for sum of numbers when rolling two dice is shown

The total possible outcome is 36

The possible number of outcome of obtaining a 4 is 3

Therefore the probability of getting a sum of 4 is

`(3)/(36)=(1)/(12)`

The possible number of outcome of obtaining a 8 is 5

Therefore the probability of getting a sum of 8 is

`(5)/(36)`

Hence the probability of getting a sum 4 or a sum of 8 is

`(1)/(12)+(5)/(36)`

This gives

`0.2`

Therefore the probability of getting a sum 4 or a sum of 8 is 0.2