Question

science test scores
what is the median of the test scores?

Explanation:

Step1: Count the number of data points

Count the number of 'X's in the plot. There are 3 + 5 + 2 + 1 + 1 + 1 + 1 + 2 + 3 + 1 = 20 data points.

Step2: Find the median position

Since there are \(n = 20\) data points (an even number), the median is the average of the \(\frac{n}{2}=10^{th}\) and \((\frac{n}{2}+ 1)=11^{th}\) ordered data points.

Step3: Order the data and find the 10th and 11th values

Counting the 'X's from the left - hand side (starting from 80):

• Up to 85: \(3 + 5=8\) 'X's
• The 9th, 10th, 11th 'X's are at 86.

Answer:

86