Thirty children were asked about the number of hours they watched TV Programmes in the previous week. The results were found as follows:
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?
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 |
Solution:
(i) A grouped frequency distribution table can be constructed as follows with the class intervals of 0 - 5, 5 - 10, 10 - 15, 15 - 20, and so on.
NUMBER OF HOURS |
NUMBER OF CHILDREN (frequency) |
0 - 5 5 - 10 10 - 15 15 - 20 |
10 13 5 2 |
TOTAL |
30 |
(ii) We can observe from the table that the number of children who watched television for 15 or more hours a week is 2 (which falls under the class interval ’15-20’).
☛ Check: NCERT Solutions for Class 9 Maths Chapter 14
Video Solution:
Thirty children were asked about the number of hours they watched TV Programmes in the previous week. The results were found as follows: 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?
NCERT Solutions for Class 9 Maths Chapter 14 Exercise 14.2 Question 8
It is given that thirty children were asked about the number of hours they watched TV Programmes in the previous week. We have prepared a grouped frequency distribution table for this data taking class width 5 and one of the class intervals as 5 - 10 and found that 2 children watched television for 15 or more hours a week.
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