Chapter 17 probability applications, The mth/probability.. sub-menu - part 1, Factorials, combinations, and permutations – HP 50g Graphing Calculator User Manual

Page 550: Chapter 17 - probability applications ,17-1, The mth/probability.. sub-menu - part 1 ,17-1, Factorials, combinations, and permutations ,17-1

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Page 17-1

Chapter 17
Probability Applications

In this Chapter we provide examples of applications of calculator’s functions to
probability distributions.

The MTH/PROBABILITY.. sub-menu - part 1

The MTH/PROBABILITY.. sub-menu is accessible through the keystroke sequence

„´. With system flag 117 set to CHOOSE boxes, the following list of
MTH options is provided (see left-hand side figure below). We have selected
the PROBABILITY.. option (option 7), to show the following functions (see right-
hand side figure below):

In this section we discuss functions COMB, PERM, ! (factorial), RAND, and RDZ.

Factorials, combinations, and permutations

The factorial of an integer n is defined as: n! = n

(n-1)

(n-2)…3

2

1. By

definition, 0! = 1. 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

Also, the number of combinations of n objects taken r at a time is

)!

/(

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)

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=

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)!

(

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!

)

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2

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n

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⎟⎟⎠

⎜⎜⎝

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