10.1. In the store, Sasha bought two pens, three notebooks, and one pencil and paid 33 rubles, Dima bought one pen, one notebook, and two pencils and paid 20 rubles. How much did Tanya pay for four pens, five notebooks, and five pencils?
Answer: 73 rubles.

Let $a, b, c$ be the price of a pen, a notebook, and a pencil, respectively. Then, according to the condition, we have $2a + 3b + c = 33$ and $a + b + 2c = 20$. Multiplying the second relation by 2 and adding it to the first equation, we get the answer.