3. To the summer math camp, 713 students traveled in 25 buses, some of which have 33 seats, and some have 26 seats. If it is known that the students filled all the seats in the buses, how many buses had 33 seats, and how many buses had 26 seats?
First method:

Assume that each of the 25 buses has 26 seats. 1 POINT

Then, they can accommodate $25 \cdot 26=\quad 1 \text{ POINT}$

$=650$ students. 1 POINT

Then, $713-650=\quad 1 \text{ POINT}$

$=63$ students would be left without seats. 1 POINT

Since $33-26=7$, a larger bus can accommodate seven more children than a smaller one. 1 POINT

Since $63: 7=9$,

9 smaller buses need to be replaced with 9 larger buses. 1 POINT

The remaining $25-9=16$ buses are smaller. 1 POINT

There were 9 buses with 33 seats and 16 buses with 26 seats. 2 POINTS

TOTAL 10 POINTS