Take any four different numbers from 0123456789, and try to find the probability that they can be arranged into a four digit even number

Take any four different numbers from 0123456789, and try to find the probability that they can be arranged into a four digit even number

The answer to this question is: 41 / 42 analysis: this question seeks the probability that any four different numbers from 0123456789 can be arranged into an even number of four digits. Then, as long as at least one of the four different numbers is even. There are 210 cases of taking any four different numbers: C (10,4) = 10! / [4! (10-4)!] = 210