4. In how many ways can an amount of 2 kuna be paid using coins of 50 lipa, 20 lipa, and 10 lipa?
4. 

| 50 | 4 | 3 | 3 | 3 | 2 | 2 | 2 | 2 | 2 | 2 | 1 | 1 | 1 | 1 | 1 |
| :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: |
| 20 | - | 2 | 1 | - | 5 | 4 | 3 | 2 | 1 | - | 7 | 6 | 5 | 4 | 3 |
| 10 | - | 1 | 3 | 5 | - | 2 | 4 | 6 | 8 | 10 | 1 | 3 | 5 | 7 | 9 |
| 50 | 1 | 1 | 1 | - | - | - | - | - | - | - | - | - | - | - |  |
| 20 | 2 | 1 | - | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - |  |
| 10 | 11 | 13 | 15 | - | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 |  |

There are 29 ways.

3 combinations are worth 1 point, and the last two and the answer are worth another point.