The number of 4-letter words, with or without meaning, each consisting of 2 vowels and 2 consonants, which can be formed from the letters of the word UNIVERSE without repetition is ________.
(432)
Vowels are U, I, E, E and consonants are N, V, R, S.
So, there are 4 vowels and 4 consonants.
When both vowels are different,
Number of ways