Rosalina and Jodie are playing a game where they roll two dice and add up the total. Rosalina says that she thinks that the total for the next roll will be 7. Jodie says that she thinks it will be more than 9. Who is more likely to be right?
Solution:
The table below shows all the possible results for rolling two dice.
| + | 1 |
2 |
3 |
4 |
5 | 6 |
| 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| 2 | 3 | 4 | 5 | 6 | 7 | 8 |
| 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| 6 | 7 | 8 | 9 | 10 | 11 | 12 |
There are six ways that the total of the dice can be exactly 7. There are also six ways that the total can be more than 9. So both girls are equally likely to be right.