15
TI36XSUS.DOC MURFE pruning--US version Pat Hatcher
Revised: 06/17/99 4:37 PM Printed: 06/17/99 4:37 PM
Page 15 of 29
Probability
A combination is an arrangement of objects in which
order is not important, as in a hand of cards.
"
¦
calculates the number of possible combinations of
n
items taken
r

at a time.

Calculate the number of 5-card poker hands that can be

dealt from a deck of 52 cards.

52
.
5
"
¦
O
2598960.
A permutation is an arrangement of objects in which
the order is important, as in a race.
(
x
calculates
the number of possible permutations of
n
items taken
r
at a time.

Calculate the number of possible permutations for the

1st-, 2nd-, and 3rd-place finishers

(

no ties

)

in an

8-horse race.

8
.
3
(
x
O
336.
A factorial is the product of the positive integers from 1
to
n
. (
n
must be a positive whole number
69.)

Using the digits 1, 3, 7, and 9 only one time each, how

many 4-digit numbers can you form?

4
"
ƒ
24.