Texas Instruments TI-73 EXPLORER - Manual (Page 57)

Chapter 2: Math Operations
51
7302ENG.DOC CH2 Math Operations, English Julie Hewlett Revised: 07/29/98 11:58 AM Printed: 05/19/99 8:58
AM Page 51 of 32
nPr nPr 1 " " 3 3
Returns the number of permutations of n items taken
r number at a time. The order in which you select the items
DOES matter. items and number can be nonnegative integers
or lists of nonnegative integers.
If both arguments are lists, they must have the same number
of elements. If one argument is a list and the other a non-list,
the non-list is paired with each element in the list, and a list of
permutations is returned.
items
nPr
number
From a group of 4 items (ABCD), how many ways can you
select 2 of the items if the order does matter?
Find 4
nPr
2.
:
4
1 " "
3
2
b
ABCD
AB AC AD
BA BC BD
CA CB CD
DA DB DC
nCr nCr 1 " " 4 4
Returns the number of combinations of n items taken
r number at a time. In combinations, the order in which you
select the items DOES NOT matter. items and number can be
nonnegative integers or lists of nonnegative integers.
If both arguments are lists, they must have the same number
of elements. If one argument is a list and the other a non-list,
the non-list is paired with each element in the list, and a list of
combinations is returned.
items
nCr
number
³
AB and BA count
as two
permutations.
4 items taken
2 at a time
permutations of