Ravi obtained 70 and 75 marks in first two unit test. Find the minimum marks he should get in the third test to have an average of at least 60 marks

Solution:

Let x be the marks obtained by Ravi in the third unit test.

Since the students should have an average of at least 60 marks,

(70 + 75 + x)/3 ≥ 60

⇒ 145 + x ≥ 180

⇒ x ≥ 180 - 145

⇒ x ≥ 35

Thus, the student must obtain a minimum of 35 marks to have an average of at least 60 marks

NCERT Solutions Class 11 Maths Chapter 6 Exercise 6.1 Question 21

Ravi obtained 70 and 75 marks in first two-unit test. Find the minimum marks he should get in the third test to have an average of at least 60 marks.

Summary:

A linear inequation (70 + 75 + x)/3 ≥ 60 can be formed. We have found that the student must obtain a minimum of 35 marks to have an average of at least 60 marks