Ramesh ranked 16th from the top and 21 from the bottom

Solution

Let's find the total number of students in Ramesh's class using the information given: Total students in the class = Ramesh's rank from the top + Ramesh's rank from the bottom - 1 (since Ramesh is counted twice) Total students = 16 + 21 - 1 = 36 Now, we know that only 21 students passed the exam. Therefore, the number of students who failed is: Total students in the class - Students who passed the exam = Students who failed 36 - 21 = 15 So, the correct answer is option 3. 15.