The average marks of a group of 30 students in a class reduces by 2 when a…
2026
The average marks of a group of 30 students in a class reduces by 2 when a good student who scored 90 marks leaves the class and a new student joins the class. Find the marks of the new student.
Answer: B. 30 marks — The average marks of 30 students decreased by 2. This means the total marks for the class decreased by 30 × 2 = 60 marks. When the student with 90 marks left…
- A.
50 marks
- B.
30 marks
- C.
35 marks
- D.
60 marks
Attempted by 35 students.
Show answer & explanation
Correct answer: B
The average marks of 30 students decreased by 2. This means the total marks for the class decreased by 30 × 2 = 60 marks.
When the student with 90 marks left and a new student joined, the total change was -60.
Let the new student's marks be x. The change in total marks is x - 90.
So, x - 90 = -60. Solving for x, we get x = 30. Therefore, the new student scored 30 marks.