1. Students Leshа and Pasha received the same scholarship for winning the olympiad and decided to spend it on repairing their rooms. Pasha bought 4 rolls of wallpaper and 4 cans of paint with all his money. Leshа bought 7 rolls of the same wallpaper and 2 cans of the same paint in the same store. At the same time, Leshа still had money left for a movie ticket. What is more expensive: a roll of wallpaper or a can of paint?
Answer: a can of paint.

Solution. Let's subtract from the purchases of Leshа and Pasha 4 rolls of wallpaper (r.ob.) and 2 cans of paint (b.kr.) each. Then it turns out that in terms of cost 2 b.kr. = 3 r.ob. + ticket, that is, 2 b.kr. cost more than 2 r.ob. Therefore, b.kr. is more expensive.

Criteria. Only answer - 0 points.