6. Ivan, Josip, and Tomislav together have 12000 kuna. Ivan divides half of his money into two equal parts and gives them to Josip and Tomislav, and keeps the other half for himself. Josip does the same, and then Tomislav, after which all three friends have the same amount of money. How much money did each boy have at the beginning?
6. Solving Backwards. $12000: 3=4000$

|  | Ivan | Josip | Tomislav |
| :---: | :---: | :---: | :---: |
| 3 | 4000 | 4000 | 4000 |
| 2 | $4000-4000: 2=2000$ | $4000-4000: 2=2000$ | $4000 \cdot 2=8000$ |
| 1 | $2000-2000: 2=1000$ | $2000 \cdot 2=4000$ | $8000-2000: 2=7000$ |
| 0 | $1000 \cdot 2=2000$ | $4000-1000: 2=3500$ | $7000-1000: 2=6500$ |

Therefore, Ivan had 2000 kn, Josip 3500 kn, and Tomislav 6500 kn.