Question

Find the median for the following data:

Marks(out of 20). Number of students
5 4
9 5
10 6
12 12
13 11
16 6
18 4
20 2

Answer 1

Answer: 12

Step-by-step explanation:

Given,

$\left\begin{array}{ccc}\text{Marks}&\text{Number of students}&\text{Cumulative Frequency}\\5&4&4\\9&5&9\\10&6&15\\\fbox{12}&\fbox{12}&27\\13&11&38\\16&6&44\\18&4&48\\20&2&50\end{array}\right$

Number  of total students = 4 + 5  + 6 + 12 + 11 + 6 + 4 + 2 = 50

Median score = n/2 = 50/2 = 25 th term

Now, Have a  look in column of  cumulative frequency after 15th term we will find 25th term i.e. between 15 and 27. We conclude that after  score of  25th term will be  12.

Hence,

Median  = 12

Answer 2

Refer to attached image

To find C•F

Multiply : 4 + 5 = 9 , 9 + 6 = 15 , 15 + 12 = 27 ...

Now

$\bf\huge => \frac{50}{2} = 25$

Hence

Median = 12

Reason => 27 comes after 25 therefore median = 12