Answer:
1/21.
Explanation:
There are 9 digits and the total number of permutations of 3 from 9 is 9P3
= 9!/6! = 504.
There are 4 even digits so the number of permutations of 3 from these 4 is 4! (4-3)! = 4*3*2 = 24.
So the required probability = 24/504
= 1/21.