Casio fx-9860GII User Manual

Using a graphic display calculator
© Oxford University Press 2012: this may be reproduced for class use solely for the purchaser’s institute
Casio fx-9860GII
Example 58
A random variable X is normally distributed with a mean of 75 and a standard
deviation of 12 or X ~ N(75, 12
2
). If P (X < x) = 0.4, fi nd the value of x.
Press
MENU
and choose 2: STAT and press
EXE
.
Press
F5
DIST
F1
NORM
F3
InvN to use the Inverse Normal function.
Press
F2
Var.
Enter Tail as Left (
F1
), Area as 0.4, σ as 12 and μ as 75.
Press
EXE
.
So if P (X < x) = 0.4 then x = 72.0 (to 3 sf).
Example 59
A random variable X is normally distributed with a mean of 75 and a
standard deviation of 12 or X ~ N(75, 12
2
).
If P ( X > x) = 0.2, fi nd the value of x.
Press
MENU
and choose 2: STAT and press
EXE
.
You are given a lower-
tail probability so you
should choose ‘Left’.
You should enter
the values: Area
(probability),
σ and μ ,
in order.
You are given an
upper-tail probability
so you should choose
‘Right’.
{ Continued on next page
54

Casio fx-9860GII Specifications

General

Type	Graphing
Form factor	Desktop
Control type	Buttons
Product color	Silver
Housing material	Plastic
Built-in capability	Yes
Digits	- digits
Display type	LCD
Second display	No
Display tilting	-
Display resolution	64 x 128 pixels
Display character size	8 x 21 mm
Display number of lines	8 lines
Display number of characters	21
Flash memory	1.5 MB
RAM capacity	0.064 MB
Storage media type	Flash
Battery type	AAA
Power source	Battery
Number of batteries supported	4