Chapter 15
Probability Distributions
In this Chapter we provide examples of applications of the
The MTH/PROBABILITY.. sub-menu - part 1
The MTH/PROBABILITY..
In this section we discuss functions COMB, PERM, ! (factorial), and RAND.
Factorials, combinations, and permutations
The factorial of an integer n is defined as: n! = n⋅
Factorials are used in the calculation of the number of permutations and combinations of objects. For example, the number of permutations of r objects from a set of n distinct objects is
n Pr = n(n − 1)(n − 1)...(n − r + 1) = n! /(n − r)!
Also, the number of combinations of n objects taken r at a time is
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