1. (20 points) Xiaohong and Xiaoming both brought money to buy the book "Fun Mathematics". When they arrived at the bookstore, Xiaohong found that she was short of 2 yuan and 2 jiao, and Xiaoming was short of 1 yuan and 8 jiao. But the money they brought together was just enough to buy one book. Then the price of "Fun Mathematics" per book is $\qquad$ yuan.
【Analysis】According to "The two of them put their money together, and it is just enough to buy a book." This indicates: The money each person lacks can be made up by the other, so the price of the book is the sum of the two people's money. The amount one person lacks is the amount the other person has, based on this to solve.

【Solution】Solution: 2 yuan 2 jiao + 1 yuan 8 jiao $=4$ yuan;
Answer: The price of each copy of "Fun Mathematics" is 4 yuan.
Therefore, the answer is: 4.

