Question

How many different arrangements can be made with the letter of the word 'M O R O C C O'?

Answer 1

Since the order matters, it's a permutation of 7 letters, but mind you in 
MOROCCO. you have 3 O's and 2 C's, Hence the arrangements are:

⁷P₇ /(3!2!) = 7!/(3!2!) = 5040/(3!2!) = 420 arrangements