Texas Instruments TI-30X IIS User Manual page 78

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 " "
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© 1999 T I
EXAS NSTRUMENTS
4! = x
3 7 9
B C D
ACBD ACDB
BCAD BCDA
CBAD CBDA
DBAC DBCA
Display
nPr nPr nCr nCr
4! 4!
I
NCORPORATED
ADBC ADCB
BDCA BDAC
CDAB CDBA
DCAB DCBA
! !
- -
&
DEG
'
24. 24.
DEG
TI-30X ÙS: A Guide for Teachers
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