In how many ways can the letters {U, R, U, R, R} be arranged?  Choose the correct option
A) 10 B) 20 C) 120 D) 720 E) 840
My answer : 10   There is 5! ways to arrange those letters in total, however letter U repeats 2! times and letter R repeats 3! times   =&gt; the way to arrange without repeating = 5!/ [2!x3!] = 10
<result>A</result>
In how many ways can the letters {U, R, U, R, R} be arranged?