the following is a sample of 20 measurements
10, 9, 5,8,13, 8, 10, 12, 11, 11, 10, 8, 10, 6, 14, 9, 13, 7, 9, 10
a. compute -
x, s2, s for this sample ( the s is squared)
x= type as integer or decimal
s2 = round to 2 decimal places (s is squared)
s = round to 2 decimal places as needed
x
=
9.65
s
2
=
5.40
s
=
2.32
b. Count the number of measurements in the interval -
x+ s, x+ 2s, x+ 3s. Express each
- - -
count as a percentage of the total number of measurements. (there is a - above the x's and
below the +'s)
The percentage of the measurements that fall within the interval -
x+ s, is ___%
13 measurements are within the interval x ± s.
The percentage is 13/20 * 100% = 65%
The percentage of the measurements that fall within the interval -
x + 2 is __%
19 measurements are within the interval x ± 2s
The percentage is 19/20 * 100% = 95%
The percentage of the measurements that fall within the interval _
x + 3s is ___%
20 measurements are within the interval x ± 3s
The percentage is 20 / 20 * 100% = 100%

c, Compare the percentages for -
x + s and the percentage given by the empirical rule:

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- Spring '98
- Dougs