5. In the math exam, Josip correctly solved 6 tasks, Danijel solved 5 tasks incorrectly, and Petar had the same number of correct and incorrect answers. How many tasks did the three of them solve together if Josip correctly solved twice as many tasks as Danijel?
5. Danijel solved twice fewer tasks than Josip, so $6: 2=3$ correct tasks.

Since Danijel had 3 correct and 5 incorrect tasks, $u$ in the exam there were $3+5=8$ tasks.

1 point

Petar solved exactly half, so he had 4 correct solutions. 1 point

The boys solved a total of 6 (Josip) +3 (Danijel) +4 (Petar) $=13$ tasks. 1 point

.$U K U P N O 4$ POINTS