Texas Instruments TI-34 II Explorer Plus - Page 91

© 1999 T
EXAS
I
NSTRUMENTS
I
NCORPORATED
TI-34 Û: A Guide for Teachers
85
Factorial (!)
H
Using the digits 1, 3, 7, and 9 only
one time each, how many 4-digit
numbers can you form?
4! = x
1379
ABCD
ABCD
BACD
CABD
DABC
ABDC
BADC
CADB
DACB
ACBD
BCAD
CBAD
DBAC
ACDB
BCDA
CBDA
DBCA
ADBC
BDCA
CDAB
DCAB
ADCB
BDAC
CDBA
DCBA
Press Display
4
H " "
nPr nCr !
¹
----
< <
4!
º
24.