4. The carpenter was making chairs. Some had 3 legs, and some had 4 legs. In total, he made 45 chairs. His daughter counted 159 legs on them. How many chairs had 3 legs, and how many had 4 legs?
4. Let's assume all chairs had 3 legs. Then there would be $3 \cdot 45=135$ legs in total. ..... 2 POINTS
The daughter counted 159 legs, which is $159-135=24$ legs more. ..... 1 POINT
This means that 24 chairs had 1 leg more, i.e., 4 legs. ..... 2 POINTS
The remaining $45-24=21$ chairs had 3 legs.
TOTAL 6 POINTS