turkey-yks 2018 Q15
Counting Arrangements with Run or Pattern Constraints
If the arrangement of letters in a word from left to right is the same as from right to left, this word is called a palindrome word.
For example; NEDEN is a palindrome word.
Engin will create a 5-letter palindrome word using each of 3 distinct vowels and 4 distinct consonants as many times as he wants. In this word, two vowels should not be adjacent and two consonants should not be adjacent either.
Accordingly, how many different palindrome words can Engin create that satisfy these conditions?
A) 72 B) 84 C) 96 D) 108 E) 120