How many four-character license plates consist of a consonant, followed by a vowel, followed by a consonant, and then a digit? (For this problem, consider Y a vowel.)
If we allow for repeats....we have
20 consonants to choose from to fill the first position
6 vowels to choose from for the second position
20 consonants to choose from for the third position
10 digits to choose from for the last position
So....the number of possible plates is
20 * 6 * 20 * 10 =
24000