Constructing A Normal Curve
Constructing A Normal Curve
Constructing A Normal Curve
The time it takes to complete a particular task (x) is normally distributed with a mean of
45 minutes with a standard deviation of 3 minutes.
Construct a graphicl model of the distribution of time.
50.75 0.0068 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
.0 . 0 .0 .0 .0 .0 .0 .0 .0 . 0 .0 . 0 .0 .0 .0 .0 . 0 .0 . 0 . 0 .0
35 36 37 38 39 40 41 42 43 44 45 46 4 7 48 49 50 51 52 53 54 55
51.00 0.0051
x
51.25 0.0037
51.50 0.0027
51.75 0.0020
52.00 0.0014
52.25 0.0010
52.50 0.0007
52.75 0.0005
53.00 0.0003
53.25 0.0002
53.50 0.0001
53.75 0.0001
54.00 0.0001
54.25 0.0000
54.50 0.0000
54.75 0.0000
55.00 0.0000
Problem 1
Use the chart wizard to draw three normal curves on one graph.
The process will be the same as was demonstrated on the sheet,
Example: Constructing a Normal Curve [ www.uh.edu/~tech132/3360n.xls ]
except I found it is best to use 'Area with a 3D visual effect.'
It is the forth box on the Chart Wizard.
Note: Before clicking on the Chart Wizard, select all 3 columns of values for f(x).
What is the effect of changing the mean? How do curves 2 and 3 differ?
What is the effect of changing the standard deviation? How do curves 2 and 1 differ?
Problem 2
The amount of instant coffee that is put into a 6 oz jar has a normal distribution with a
standard deviation of 0.03. oz.
x f(x) P(X<x)
5.90 0.0514 0.000
5.91 0.1477 0.001
5.92
5.93
5.94
5.95
5.96
5.97
5.98
5.99
6.00
6.01