Casio fx-9860GII - 5.13 Calculating Poisson probabilities

Using a graphic display calculator
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Casio fx-9860GII
b When using the lower bound probability to calculate other probabilities,
it is easier to do this without the wizard.
Press
MENU
. Choose 1: RUN·MAT and press
EXE
.
P(5 ≤ X ≤ 15) = P(X ≤ 15) – P(X ≤ 4)
Press
OPTN
F5
STAT |
F3
DIST |
F5
BINM to enter the binomial
menu.
Enter binominalCD(15, 20, 0.45) – binominalCD(4, 20, 0.45)
P(5 ≤ X ≤ 15) = 0.980 (to 3 sf )
c P(X > 11) = 1 – P(X ≤ 11)
Enter 1 – binominalCD (11, 20, 0.45)
P (X > 11) = 0.131 (to 3 sf )
Calculating Poisson probabilities
5.13 Calculating Poisson probabilities
Example 55
X is a discrete random variable and X ~ Po (0.5)
Calculate
i P(X = 2)
ii P(X ≤ 2)
iii P(X > 2)
i
PX
e
()
.
(.)
!
==
−
×
2
05 2
05
2
The calculator can fi nd this value directly.
Press
MENU
and choose 2: STAT and press
EXE
.
Press
F5
DIST |
F6
|
F1
POISN|
F1
Ppd to use the Poisson
probability density function.
Enter the X value and the parameter.
Leave Data as Variable and Save Res as None.
Select Execute and press
EXE
.
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