How many different signals can be made with 5 flags from 8 flags of different colors?

Question

trying to figure out these probabilities

 

Answer 1

This requires use of a Permutation formula ... you are taking 5 flags at a time, from a group of 8 flags.

The formula is as follows:

 

nPr = n!/(n - r)!

 

n = 8 ... the total number of flags ... r = 5 ... the number of flags you are taking each time

 

8P5 = 8!/(8-5)!

       = 8!/3!

       = (8)(7)(6)(5)(4)3!/3!

       = (8)(7)(6)(5)(4)

       = 6720