Question 1016875
 
Question:
How many 4-digits even passcode can be formed from no. 0,3,5,7,9 w/o repitition?
 
Solution:
 
The only way we get even number out of the given 5 digits is to end the code with a zero.
Since there is no repetition allowed, we are left with choosing 3 digits out of the remaining 4 digits (3,5,7,9).
The number of permutations is therefore 4*3*2=24.