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# 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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