1. The lengths of fifty seeds are measured by a garden centre, in millimetres. The data is summarised below:
Length of seeds (mm)
|
0 -
|
3 -
|
6 -
|
9 -
|
15 − 21
|
Frequency
|
5
|
10
|
17
|
14
|
4
|
a. Draw a histogram to show these measurements.
b. Complete the following cumulative frequency table and draw a cumulative frequency graph.
Length of seed
(x mm) |
Cumulative frequency
(< x) |
0
|
|
3
|
|
6
|
|
9
|
|
15
|
|
21
|
2. The percentage spending on items of household expenditure is shown below. Display this information on a pie or sector graph.
Item |
Housing
|
Food
|
Entertainment
|
Power
|
Transport
|
Other
|
% of spending |
40
|
32
|
5
|
5
|
10
|
8
|
3. The length of life in hours of 250 florescent light tubes are shown below.
Life of tube (hours)
|
Frequency
|
700 − 799
|
23
|
800 − 899
|
43
|
900 − 999
|
55
|
1000 − 1099
|
78
|
1100 − 1199
|
30
|
1200 − 1499
|
21
|
a. Draw a histogram to show this data.
b. Construct a cumulative frequency table and use it to sketch a cumulative frequency graph.
c. From the cumulative frequency graph, estimate:
(i) The median
(ii) The lower quartile
(iii) The upper quartile
(iv) The 90the percentiled. Use the cumulative frequency graph to estimate how many of the 250 tubes would you expect to last more than 850 hours.