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Question
Thirty children were asked about the number of hours they watched T.V. programmers in the previous week. The results were found as follows:
| 1 | 6 | 2 | 3 | 5 | 12 | 5 | 8 | 4 | 8 |
| 10 | 3 | 4 | 12 | 2 | 8 | 15 | 1 | 17 | 6 |
| 3 | 2 | 8 | 5 | 9 | 6 | 8 | 7 | 14 | 12 |
(i) Make a grouped frequency distribution table for this data, taking class width 5 and one of the class intervals as 5 – 10.
(ii)How many children watched television for 15 or more hours a week?
Solution
(i) Class intervals will be 0-5,5-10,10-15,............
The grouped frequency distribution table is as follows
| Hours | Number of children |
| 0-5 | 10 |
| 5-10 | 13 |
| 10-15 | 5 |
| 15-20 | 2 |
| Total | 30 |
(ii) The number of children, who watched TV for 15 or more hours a week is 2 (i.e.,number of children in class interval 15-20 ).
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