© 1999
T
EXAS
I
NSTRUMENTS
I
NCORPORATED
TI-30X
Ù
S: A Guide For Teachers
70
Permutation (nPr)
H
Four different people are running in
a race. Use this formula to find how
many different ways they can place
1
st
and 2
nd
.
4 nPr 2 = x
A
B
C
D
AB and BA
count as 2
permutations.
AB AC AD
BA BC BD
CA CB CD
DA DB DC
Press Display
4
H
nPr
nCr
!
¹
---
DEG
2
<
4 nPr 2
'
12.
DEG