Refer to Table 14.7, Chapter 14.
i) Find the probability that a student obtained less than 20% in the mathematics test.
ii) Find the probability that a student obtained marks 60 or above.
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 students in a particular range of marks = Number of students in that range / Total number of students
Total number of students = 90
It is given that the test is out of 100 marks so 20% would mean 20 marks
Number of students that obtained less than 20% marks = 7
Number of students that obtained 60 marks or above = 15 + 8 = 23
i) Probability of students that obtained less than 20% marks = 7/90
ii) Probability of students that obtained 60 marks or above = 23/90
☛ Check: Class 9 Maths NCERT Solutions Chapter 15
Video Solution:
Refer to Table 14.7, Chapter 14. i) Find the probability that a student obtained less than 20% in the mathematics test. ii) Find the probability that a student obtained marks 60 or above.
NCERT Solutions for Class 9 Maths Chapter 15 Exercise 15.1 Question 6
Summary:
The data of marks obtained by students in mathematics is given. We have found that the probability of students that obtained less than 20% marks = 7/90 and the probability of students that obtained 60 marks or above = 23/90.
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