Out of the four annual examinations each with a total of 200 marks a student secured average marks o...........

Explanation:

Let the average marks in the third Annual examination be x.
Total marks = (Marks in first + second + third + forth) Annual examination 4(60)(200/100)=(45/100)(200)+(50/100)(200)+(55/100)(200)+(x/100)(200) 4(60)=45+50+55+x 
x=90
So, the student must score 90% in the fourth annual examination to secure 60% overall average. ∴ Average marks in the fourth annual examination (90100)×200=180 marks.