In how many ways can the letters {U, R, R, R, R} be arranged?	Options.
A) 5  B) 20  C) 120  D) 720  E) 840
My answer : 5   There is 5! ways to arrange those letters in total, however letter U repeats 1! times and letter R repeats 4! times   =&gt; the way to arrange without repeating = 5!/ [1!x4!] = 5
<result>A</result>
In how many ways can the letters {U, R, R, R, R} be arranged?