Find the number of ways to arrange the letters in each of th
     Find the number of ways to arrange the letters in each of the following words. Assume all letters are lowercase.  b. Radar.  d. Mississippi. 
  
  Solution
b. 5 letters so 5! =120 arrangements but there are repeated letters so some arrangements are counted more than once.
For each letter repeated m times we divide by m!
Here, in Radar r is repeated 2 times and a is repeated 2 times so we divide by: 2!*2!=4
So number of arrangments is
120/4=30
b.
11 letters so 11! arrangements
i is repeated 4 times
s is repeated 4 times
p is repeated 2 times
So we divide by: 4!*2!*2!=96
So number of arrangements is: 11!/96=415800

