1. For each of the following sets of data find:
(i) the median
(ii) the lower quartile
(iii) the upper quartile
(iv) the interquartile range
(v) the range
(vi) the mean (use calculator).Give answer to 3 significant figures(vii) standard deviation (use calculator). Give answers to 3 significant figures.
a. 5, 4, 3, 7, 8, 15, 12, 14, 20, 23, 44
b. $12.48, $18.20, $16.20, $20.60, $5.04, $22.49
c. 5.4, 6.6, 7.2, 9.6, 3.6, 9.8, 4.2
d. 90, 44, 78, 54, 62, 84, 88, 58, 42, 76, 88, 52, 36
e. 1.48 kg , 924 g , 9200 cg , 986 g , 824 000 mg , 0.5 kg , 7100 cg
2. For the following set of data find the find the 10th and 90th percentiles.
8, 8, 12, 14, 16, 20, 25, 27, 29, 30, 39, 41, 46, 49, 50, 51, 54, 56, 60, 65,
3. Find the mean of 12, 14, 17, 20, 21, 24 and complete the table below to help to find the standard deviation.
|
x
|
x −
 |
(x −
)2 |
|
12
|
||
|
14
|
||
|
17
|
||
|
20
|
||
|
21
|
||
|
24
|
||
|
Total Σ(x −
)2 = |
4. Find the mean and standard deviation of the following frequency distribution. Complete the table to assist your calculation.
|
x
|
f
|
x −
|
(x −
)2 |
f(x −
)2 |
|
1
|
4
|
|||
|
2
|
6
|
|||
|
3
|
9
|
|||
|
4
|
5
|
|||
|
5
|
1
|
|||
|
Σ
|
5. Use the formula 
to find the standard deviation of the data 3, 5, 6, 7, 9, 10, 12, 15, 20.
6. Use the formula 
to find the standard deviation of the following frequency distribution.
|
x
|
f
|
|
5
|
5
|
|
6
|
8
|
|
7
|
12
|
|
8
|
7
|
|
9
|
4
|
