How do you make 24 using 2 2 21 22?

To make 24 using the numbers 2, 2, 21, and 22, you can use the following mathematical expression: (22 - 21) + 2 + 2 = 24. This equation breaks down as follows: subtracting 21 from 22 gives you 1, then adding the two 2s results in 4, and finally adding 1 to 4 equals 24.