1. A cyclist covered a certain distance in 1 hour and 24 minutes at a constant speed of $30 \mathrm{~km} / \mathrm{h}$. At what speed did he travel on the return trip if he traveled 12 minutes less?
First method:
The cyclist in 1 hour and 24 minutes, which is 1.4 hours ..... 1 POINT
traveled a distance of $1.4 \cdot 30=42 \mathrm{~km}$. ..... 1 POINT
On the return trip, he traveled for 1 hour and 12 minutes ..... 1 POINT
which is 1.2 hours. ..... 1 POINT
The speed on the return trip was $42: 1.2=35 \mathrm{~km} / \mathrm{h}$. ..... 2 POINTS
TOTAL 6 POINTS