Passage Based Questions: Quantitative Aptitude - 7

Average marks obtained in Physics by all the seven students
= 1/7 x [(90% of 120) + (80% of 120) + (70% of 120) + (80% of 120) + (85% of 120) + (65% of 120) + (50% of 120)]
= 1/7 x [(90 + 80 + 70 + 80 + 85 + 65 + 50)% of 120]
= 1/7 x [520% of 120]
= 624/7 
= 89.14.

Aggregate marks obtained by Sajal
= [(90% of 150) + (60% of 130) + (70% of 120) + (70% of 100) + (90% of 60) + (70% of 40)]
= [135 + 78 + 84 + 70 + 54 + 28]
= 449.

Aggregate marks obtained by Tarun
= [ (65% of 150) + (35% of 130) + (50% of 120) + ((77% of 100) + (80% of 60) + (80% of 40) ]
= [ 97.5 + 45.5 + 60 + 77 + 48 + 32 ]
= 360.
The maximum marks (of all the six subjects)
= (150 + 130 + 120 + 100 + 60 + 40)
= 600.

From the table it is clear that Sajal and Rohit have 60% or more marks in each of the six subjects.

We shall find the overall percentage (for all the seven students) with respect to each subject.
The overall percentage for any subject is equal to the average of percentages obtained by all the seven students since the maximum marks for any subject is the same for all the students.
Therefore, overall percentage for:
(i) Maths

(ii) Chemistry

(iii) Physics

(iv) Geography

(v) History

(vi) Comp. Science 

Clearly, this percentage is highest for Maths.