Correct Answer - Option 2 : 160
Given:
Percentage of students who were preparing for IIT-JEE = 60%
Total number of students who were not preparing for IIT-JEE = 64
Calculations:
Let the total number of student in the classroom be 100x
Total number of students who were preparing for IIT-JEE = 100x × 60/100 = 60x
Total number of students who were not preparing for II-JEE = 100x – 60x = 40x
⇒ 40x = 64
⇒ x = 64/40 = 8/5
The total number of students = 100x = 100 × 8/5 = 160
∴ The total number of students in the classroom is 160