Question

An experiment consists of rolling two fair dice and adding the dots on the two sides facing up. Find the probability of the sum of the dots indicated. A sum less than 6

Answer 1

There are 36 total possible outcomes (6 outcomes per die).

First count the number of ways two positive integers can add up to 5:

1 + 4
2 + 3
3 + 2
4 + 1

With only four possibilities, the probability of rolling a sum smaller than 6 is then
`\frac4{36}=\frac19\approx0.11`.