Texas Instruments TI-34 II Explorer Plus User Manual page 91

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