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?

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.

(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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