There are 11 factorial, or 39,916,800 permutations of the letters in the word PROBABILITY. However, because the letters B and I are duplicated, there are only one quarter of that, or 9,979,200 distinguishable permutations.
There are 30 ways.
60
Once...its true!
360
mad adam dam am
There are 3360 ways.
You can arrange and rearrange the word as many times as you like!There are 5040 different ways.
Fix X then you are left with 10 letters, so you have 10! ways to arrange
There are 30 ways.
24 ways
362,880 ways
24
60
10080
15
One... numbers
12