Data Interpretation - Table Charts

The following table gives the percentage of marks obtained by seven students in six different subjects in an examination.

The Numbers in the Brackets give the Maximum Marks in Each Subject.

Student Subject (Max. Marks)
Maths Chemistry Physics Geography History Computer Science
(150) (130) (120) (100) (60) (40)
Ayush905090607080
Aman1008080408070
Sajal906070709070
Rohit806580806060
Muskan806585955090
Tanvi707565854060
Tarun653550778080

1. 

What are the average marks obtained by all the seven students in Physics? (rounded off to two digit after decimal)

A. 77.26
B. 89.14
C. 91.37
D. 96.11

Answer: Option B

Explanation:

Average marks obtained in Physics by all the seven students

 
= 1 x [ (90% of 120) + (80% of 120) + (70% of 120)
7
              + (80% of 120) + (85% of 120) + (65% of 120) + (50% of 120) ]
= 1 x [ (90 + 80 + 70 + 80 + 85 + 65 + 50)% of 120 ]
7
= 1 x [ 520% of 120 ]
7
= 624
7
= 89.14.


2. 

The number of students who obtained 60% and above marks in all subjects is?

A. 1
B. 2
C. 3
D. None

Answer: Option B

Explanation:

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


3. 

What was the aggregate of marks obtained by Sajal in all the six subjects?

A. 409
B. 419
C. 429
D. 449

Answer: Option D

Explanation:

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.


4. 

In which subject is the overall percentage the best?

A. Maths
B. Chemistry
C. Physics
D. History

Answer: Option A

Explanation:

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
= [ 1 x (90 + 100 + 90 + 80 + 80 + 70 + 65) ] %
7
= [ 1 x (575) ] %
7
= 82.14%.
(ii) Chemistry
= [ 1 x (50 + 80 + 60 + 65 + 65 + 75 + 35) ] %
7
= [ 1 x (430) ] %
7
= 61.43%.
(iii) Physics
= [ 1 x (90 + 80 + 70 + 80 + 85 + 65 + 50) ] %
7
= [ 1 x (520) ] %
7
= 74.29%.
(iv) Geography
= [ 1 x (60 + 40 + 70 + 80 + 95 + 85 + 77) ] %
7
= [ 1 x (507) ] %
7
= 72.43%.
(v) History
= [ 1 x (70 + 80 + 90 + 60 + 50 + 40 + 80) ] %
7
= [ 1 x (470) ] %
7
= 67.14%.
(vi) Comp. Science
= [ 1 x (80 + 70 + 70 + 60 + 90 + 60 + 80) ] %
7
= [ 1 x (510) ] %
7
= 72.86%.

Clearly, this percentage is highest for Maths.


5. 

What is the overall percentage of Tarun?

A. 52.5%
B. 55%
C. 60%
D. 63%

Answer: Option C

Explanation:

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.

Therefore Overall percentage of Tarun = ( 360 x 100 ) % = 60%.
600