A study was conducted to find out the concentration of sulphur dioxide in the air in parts per million (ppm) of a certain city. The data obtained for 30 days is as follows:
i) Make a grouped frequency distribution table for this data with class intervals as 0.00 - 0.04, 0.04 - 0.08, and so on.
ii) For how many days, was the concentration of sulphur dioxide more than 0.11 parts per million?

Solution:

(i) A grouped frequency distribution table with a class size of ‘0.04’ needs to be constructed for the given data.

(ii) From the above table, we can see that the number of days during which the concentration of sulphur dioxide is more than 0.11 ppm falls over three class intervals, 0.12 - 0.16, 0.16 - 0.20, and 0.20 - 0.24.

So, 2 + 4 + 2 = 8

Thus, 8 days had a concentration of sulphur dioxide more than 0.11 ppm.

☛ Check: Class 9 Maths NCERT Solutions Chapter 14

Video Solution:

A study was conducted to find out the concentration of sulphur dioxide in the air in parts per million (ppm) of a certain city. The data obtained for 30 days is as follows: i) Make a grouped frequency distribution table for this data with class intervals as 0.00 - 0.04, 0.04 - 0.08, and so on. ii) For how many days was the concentration of sulphur dioxide more than 0.11 parts per million?

NCERT Solutions for Class 9 Maths Chapter 14 Exercise 14.2 Question 5

Summary:

A study was conducted to find out the concentration of sulphur dioxide in the air in parts per million (ppm) of a certain city. The data obtained for 30 days is given. A grouped frequency distribution table for this data with class intervals as 0.00 - 0.04, 0.04 - 0.08 has been created. We have found that 8 days had a concentration of sulphur dioxide more than 0.11 ppm.

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