1. From two settlements, which are 60 km apart, two cars set off in the same direction at the same time. The first car, traveling at a speed of 90 km/h, caught up with the second car after three hours. What is the speed of the second car?
Solution. The closing speed of the cars is $60: 3=20(\kappa m / h)$, so the speed of the second car is $90-20=70(km / h)$.

Answer: 70 km $/$ h.

Comment. The correct answer was obtained through correct reasoning - 7 points. The closing speed was correctly found, but the wrong answer was given - 3 points.