Question

6. The following table shows the frequency distribution of 100 students by marks obtained in an
examination
Marks Obtained :
10-20 20-30 30-40 40-50 50-60 60-70 70-80
No. of Students
1
8
18
36
20
10
7
on scrutiny the following mistakes of tabulation were revealed :
Student :
A B C D E F
Correct Marks :
76
62
85
Marks Entered :
55 66 16 32 58 75
Revise the frequency table and calculate correct arithmetic mean.
45
36
48
ANSWERS​

Answer 1

Answer:

To revise the frequency table, the correct marks of the students need to be placed in the appropriate interval. The revised frequency table will look like this:

Marks Obtained :

10-20 20-30 30-40 40-50 50-60 60-70 70-80

No. of Students

1

8

18

25

22

14

12

To calculate the correct arithmetic mean, the sum of the marks of all 100 students and the number of students need to be known. Since this information is not provided, it is not possible to calculate the correct arithmetic mean.