Question

The median of first $16$ prime numbers is ...........

• A. $12$
• B. $24$
• C. $21$
• D. $30$

Answer 1

The correct option is C $21$

Median is the middle value of the data values after arranging the data values in the ascending or descending order.

If $n$ is odd, then the median is $(\frac{n+1}{2}{)}^{th}$ value.

If $n$ is even, then the median is ${\frac{(\frac{n}{2}{)}^{th}+(\frac{n}{2}+1)}{2}}^{th}$ value.

The first $16$ prime numbers are $2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53$

Given that number of prime numbers is $n=16$ (even) then

the median is $\left(\frac{(\frac{16}{2}{)}^{th}+(\frac{16}{2}+1{)}^{th}}{2}\right)$ value = $\frac{8^{th}+9^{th}}{2}$ =$\frac{19+23}{2}$=$\frac{42}{2}=21$