Question

Ezra counts the number of passengers who are already on the bus when he gets on each morning. His data for the last 15 days are shown below. What is the interquartile range of the data?

Answer 1

6

Explanation:

Answer 2

6

Explanation:

The data is

8,9,9,10,12,12,13,14,15,15,15,16,18,19,20

There are 15 data points

The median is the 15/2 = 7.5 rounding to 8

The 8th data point

8,9,9,10,12,12,13, 14, 15,15,15,16,18,19,20

Take the 7 points on the left and divide in half

Take the 7 points on the right and divide in half

8,9,9, 10 ,12,12,13, 14, 15,15,15, 16, 18,19,20

The interquartile range is the middle of the upper half of the data minus the middle of the lower half of the data

16 - 10 = 6