Question

The marks obtained by 60 students in a certain test are given below:

Marks: 10–20, 20–30, 30–40, 40–50, 50–60, 60–70, 70–80, 80–90, 90–100
No. of students: 2, 3, 4, 5, 6, 12, 14, 10, 4

Median of the above data is

• A. 68.33
• B. 70
• C. 68.11
• D. None of these

Hint:

Median class is the class whose cumulative frequency just exceeds (N)/(2).

Answer 1

The Correct Option is A

Step 1: Total number of students N = 60. (N)/(2) = 30 

Step 2: Cumulative frequencies show that the median class is 60-70. 

Step 3: Using median formula: Median = l + (((N)/(2)-cf)/(f))h where l=60, cf=20, f=12, h=10 Median = 60 + ((30-20)/(12))10 = 60 + 8.33 = 68.33