In Q.5, Exercise 14.2, you were asked to prepare a frequency distribution table, regarding the concentration of sulphur dioxide in the air in parts per million of a certain city for 30 days. Using the table, find the probability of the concentration of sulphur dioxide in the interval 0.12 – 0.16 on any of these days.

Solution:

The probability of certain event is given by the ratio of occurrence of a particular event by the total number of events.

Probability of an event, P(E) = Number of instances that event takes place/Total number of instances

Total number of days = 30

Number of days on which concentration of sulphur dioxide was in the interval 0.12 – 0.16 = 2

Probability of the concentration of Sulphur dioxide in the interval 0.12 – 0.16 = 2/30 = 1/15

☛ Check: Class 9 Maths NCERT Solutions Chapter 15

Video Solution:

In Q.5, Exercise 14.2, you were asked to prepare a frequency distribution table, regarding the concentration of sulphur dioxide in the air in parts per million of a certain city for 30 days. Using the table, find the probability of the concentration of sulphur dioxide in the interval 0.12 – 0.16 on any of these days.

NCERT Solutions for Class 9 Maths Chapter 15 Exercise 15.1 Question 12

Summary:

We have found that the number of days on which concentration was in the interval 0.12 – 0.16 = 2 and the probability of the concentration of Sulphur dioxide in the interval 0.12 – 0.16 = 2/30 = 1/15.

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