8.1. Pasha and Sasha made three identical toy cars. Sasha did one-fifth of the total work. After selling the cars, they divided the proceeds in proportion to the work done. Pasha noticed that if he gave Sasha 400 rubles, and Sasha made another such car and sold it, they would have the same amount of money. How much does one car cost?
Answer: 1000 rubles.

Solution: Sasha did one-fifth of the entire work, which means he made 0.6 of one car, while Pasha did the remaining 2.4. That is, the difference is 1.8 cars. If Sasha makes another car, the difference will be 0.8 of one car. Pasha gave 400 of his rubles, thereby reducing the amount of money he had by 400 rubles and increasing the amount of money Pasha had by the same amount. That is, he changed the difference in the amount of money between one and the other by 800 rubles. Thus, 0.8 of a car corresponds to 800 rubles. Therefore, a whole car costs 1000 rubles.

Criteria: Only the answer - 0 points.

Answer with verification - 1 point.

Solution, in which 0.8 of a car corresponds to 400 rubles - no more than 2 points.