The water bills (in rupees) of houses in a certain street for the period 1.1.98 to 31.3.98 are given below:
56, 43, 32, 38, 56, 24, 68, 85, 52, 47, 35, 58, 63, 74, 27, 84, 69, 35, 44, 75, 55, 30, 54, 65, 45, 67, 95, 72, 43, 65, 35, 59
Tabulate the data and present the data as a cumulative frequency table using 70-79 as one of the class intervals.
The minimum bill is Rupees 24
And, the maximum bill is Rupees 95
Range = Maximum bill – Minimum bill
= 95 – 24 = 71
Given, class interval is 70-79. So, class size = 79 – 70
= 9
Therefore, Number of classes = =
= 7.80 = 8
The cumulative frequency distribution table is as follows:
Bills | No. of houses (Frequency) | Cumulative frequency |
16-25 | 1 | 1 |
25-34 | 3 | 4 |
34-43 | 5 | 9 |
43-52 | 4 | 13 |
52-61 | 7 | 20 |
61-70 | 6 | 26 |
70-79 | 3 | 29 |
79-88 | 2 | 31 |
88-97 | 1 | 32 |