4. The sum of the digits of an odd four-digit number is 11. The sum of the digits in the units and tens place is 5. How many such numbers are there?
4. The unit digit must be an odd number, and together with the tens digit, it gives 5. We have three possibilities: 41, 23, or 05.

4 points

The sum of the first two digits must be $11-5=6$.

There are 6 possibilities for them: 60, 51, 42, 33, 24, and 15.

The number of desired numbers is $3 \cdot 6=18$. 3 points