In Q.1, Exercise 14.2, you were asked to prepare a frequency distribution table regarding the blood groups of 30 students of a class. Use this table to determine the probability that a student of this class, selected at random, has blood group AB.

Solution:

The probability of a 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 students = 30

Number of students having blood group AB = 3

Probability of students having blood group AB = (Number of students having blood group AB) / Total number of students = 3/30 = 1/10

☛ Check: NCERT Solutions for Class 9 Maths Chapter 15

Video Solution:

In Q.1, Exercise 14.2, you were asked to prepare a frequency distribution table regarding the blood groups of 30 students of a class. Use this table to determine the probability that a student of this class, selected at random, has blood group AB.

NCERT Solutions for Class 9 Maths Chapter 15 Exercise 15.1 Question 13

Summary:

The data of blood groups of 30 students is given. We have found that the probability of students having blood group AB = (Number of students having blood group AB) / Total number of students = 3/30 = 1/10

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