How to do the math problem in senior high school?
This is a question of probability and statistics. Sort out four numbers from five numbers. I think the way to do this is: to be divisible by 2, the last digit may be 0, 2, 4. When it is 0, add A43 before it (that is, sort out three numbers from four numbers); When it is 2 or 4, the calculation method is the same, which can be divided into two situations: choosing 0 and not choosing 0. C2 132a22+A33, then the final result is A43+2 (C2 132a22+A33) = 84.