EasyStatistics & Data ScienceHigh School (9–10)High School (11–12)UndergraduateGeneralStatistics Basics › Spread of DataStatistics Basics › Tables and GraphsNumerical
A commuter records her journey times, in minutes, on two bus routes over a made-up month…
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
A commuter records her journey times, in minutes, on two bus routes over a made-up month. The five-number summaries are: route A 18, 24, 27, 31 and 40; route B 20, 22, 29, 33 and 52. How much higher is the median of route B? What is the IQR of each route? Which route is more predictable, and why?
Need a reminder? The key ideaShow
Compare groups by centre (median), spread (IQR and range), shape and outliers, on one shared axis. A median above the other group's means at least half of one group is above about three quarters of the other.
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. Centres. minutes.
Step 2. Spreads. Route A: minutes. Route B: minutes.
Answer: 2 minutes, 7 minutes and 11 minutes. Route A is more predictable: its middle half covers a narrower range of times, and its longest journey is 40 minutes against 52.
Check. Route B also has a long right whisker, so a few of its journeys took much longer than usual.
Discussion (0)
Log in to join the discussion.
Loading…