Question

The marks obtained by Andrew in $7$ tests are recorded as, $1,9,3,5,4,11$, and $9$.
With respect to the given data, find which of the following options are correct?

• A. $\text{Mean}=6$
• B. $\text{Median}=6$
• C. $\text{Median}=5$
• D. $\text{Mean}=5$

Answer 1

Answer: (A), (C)

$\text{Median}=5$

The mean of the given set is calculated as,

$\begin{array}{cc}\text{Mean}& =\frac{\text{Sum of all the values}}{\text{Total number of values}}\\ & =\frac{1+9+3+5+4+11+9}{7}\\ & =\frac{42}{7}\\ & =6\end{array}$

There are $7$ numbers in total.
Since the total number of values is odd, therefore the median will be the middle number after arranging the given numbers in an ascending order.

The given numbers arranged in the ascending order are as follows:
$1,3,4,5,9,9,11$.
Here, the middle number is $5$.

Thus, the median of the given data set of numbers is $5$.