Answer:
For the average to be above 90, the marks in the fourth paper should be MORE THAN 92.
Step-by-step explanation:
The score of students in last 3 exams = 89 , 87 and 92
Let us assume the marks scored by the student in last exam = k
The average of marks should be above 90.
Now, [tex]\textrm{The average of total marks} = \frac{\textrm{Sum of all marks obtained in 4 papers}}{\textrm{ 4 papers }}[/tex]
Sum of all 4 paper's marks = 89 + 87 + 92 + k = 268 + k
Also, 90 < Average
[tex]\implies 90 < \frac{268 + k}{4}\\ or, 360 < 268 + k\\\implies 360 - 268 < k\\or, k > 92[/tex]
Hence,for the average to be above 90, the marks in the fourth paper should be MORE THAN 92.
