User manual

© 1999 T
EXAS
I
NSTRUMENTS
I
NCORPORATED
TI-30X ÙS: A Guide for Teachers
70
Four different people are running in
a race. Use this formula to find how
many different ways they can place
1st and 2nd.
4 nPr 2 = x
ABC D
H
AB and BA
count as 2
permutations.
AB AC AD
BA BC BD
CA CB CD
DA DB DC
Press Display
4 H
nPrnPr nCrnCr ! !
&
------
DEG
2 <
4 nPr 24 nPr 2
'
12.12.
DEG
Permutation (nPr)