1. Variant 1.

Petya has four cards with digits $1,2,3,4$. Each digit appears exactly once. How many natural numbers greater than 2222 can Petya make from these cards?
Answer: 16.

Solution: Let's find out how many different numbers can be formed from these cards: the first digit can be chosen in 4 ways, the second can be appended in 3 ways, the third in 2 ways, and the last one is uniquely determined. That is, a total of 24 different numbers can be obtained (it is also possible to verify this explicitly by listing all suitable numbers). Let's find out how many of the listed numbers will not suit us. These are all numbers starting with 1, there are 6 of them. And 2 more numbers: 2134, 2143, because if the number starts with 2, the second digit can only be 1. Then the suitable numbers are $24-6-2=16$.