Statistics
The button pressing sequence for statistics is on pages 12 to 15.
Remember!
∙When you have finished entering the data you must press Cto tell the calculator that you have completed entering the scores.
∙When you press SHIFT14 then 2to bring up the value of the mean you must press pto display the value. This is particularly important when you proceed to find the second piece of information, e.g. the standard deviation.
Practise your statistics skills with the following questions.
1Set your calculator to statistics and turn the frequency list off. A Enter the scores 16, 19, 5, 11, 15, 12 and 9.
B Determine the value of the mean, ( x ) to 2 decimal places.
C What is the value of the standard deviation (σ n ) to 3 decimal places? D Determine the sample standard deviation (σ n−1 ) correct to 3 decimal
places.
2Clear the data in the statistics list. The easiest way to clear the data is to turn the calculator off. Alternatively, set the calculator to comp then back to statistics.
3Set the calculator to statistics with the frequency on.
AEnter the data in the table into the calculator.
Scores | Frequency |
5 | 4 |
6 | 9 |
7 | 15 |
8 | 11 |
9 | 7 |
10 | 4 |
BDetermine the size of n, the number of scores.
CWhat is the value of the mean?
DDetermine the size of the standard deviation correct to 3 decimal places.
4Determine the mean and standard deviation of the scores in the following table.
| Scores | 10 | 11 | 12 | 13 | 14 | 15 | 16 | ||
| Frequencies | 15 | 12 | 5 | 8 | 10 | 13 | 6 | ||
Answers |
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1B | x | = 12.43, σ n = 4.338, | σ n−1 | = 4.685 | 3B n = 50 | C | x | = 7.4 | D σ n = 1.356 | |
4x = 12.7 , σ n = 2.079
© Sue Thomson and Shriro Australia PTY Limited. This page may be photocopied for classroom use.
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