How many of these contain the letter P?
If the order of the three letters doesn't matter, this is a combination.
There are altogether 13 letters in the word PARALLELOGRAM, but only 8 different ones.
1. If the selection has all different letters, there are (3)C(8) combinations:
(3)C(8) = ...
The number of different selections of three letters which can be made from the letters of the word PARALLELOGRAM are calculated.