- #1

jaus tail

- 615

- 48

## Homework Statement

4 dice are rolled. Find probability that sum is 20.

## Homework Equations

If a dice is rolled the outcome can be 1, 2, 3, 4, 5, 6

## The Attempt at a Solution

Well the combinations for sum to be 20 are:

5, 5, 5, 5 = 20

5, 5, 6, 4 = 20

6, 6, 5, 3 = 20

6, 6, 4, 4 = 20

6, 6, 6, 2 = 20

Total outcomes is 6 * 6 * 6 * 6

I don't know how to calculate number of favorable outcomes.

I mean with combination 5, 5, 5, 5 only 1 arrangement is possible that is all dice is 5.

How to proceed with 5, 5, 6, 4 and other combinations?

Thanks in advance.