6. the table shows the number of students in each group on a school field trip. find the median size of a…

Explanation:

Step1: Arrange data in ascending order

$4,4,4,5,5,5,5,5,6,6,6,7,7,7,7,7,8,8,9,9$

Step2: Determine the number of data points

There are $n = 20$ data - points.

Step3: Use the median formula for even - numbered data set

The median for an even - numbered data set is the average of the $\frac{n}{2}$th and $(\frac{n}{2}+1)$th ordered data points. Here, $\frac{n}{2}=\frac{20}{2}=10$ and $\frac{n}{2}+1 = 11$. The 10th value is $6$ and the 11th value is $6$. Median=$\frac{6 + 6}{2}$

Answer:

$6$