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 **