On Uncle Fyodor's birthday, Postman Pechkin wants to find out how old he is. Sharik says that Uncle Fyodor is more than 11 years old, and cat Matroskin claims that he is more than 10 years old. How old is Uncle Fyodor, given that exactly one of them is wrong? Justify your answer.
Note that if Sharik did not make a mistake, then Matroskin did not make a mistake either, which contradicts the condition. Therefore, Sharik must have lied, while Matroskin told the truth. Thus, Uncle Fyodor is more than 10 years old, but not more than 11. Therefore, Uncle Fyodor is 11 years old.

## Problem