MediumStatistics & Data ScienceMiddle Stage (6–8)High School (9–10)High School (11–12)UndergraduateGeneralStatistics Basics › Tables and GraphsConceptual
The 18 race times of the last problem are drawn as a histogram three times: with 2 bars, with 4…
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
The 18 race times of the last problem are drawn as a histogram three times: with 2 bars, with 4 bars and with 18 bars.
- What does each one show?
- Which is best, and why?
Need a reminder? The key ideaShow
A histogram shows numbers put in groups of equal width. The bars touch, and the height of a bar is the number of values in its group. A line graph joins values over time.
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. Two bars. Groups of about 7 s. Almost everyone lands in one bar, and the shape is lost.
Step 2. Eighteen bars. Groups under 1 s wide. Most bars hold 0 or 1 runner, so the picture is ragged.
Step 3. Four bars. Groups of 5 s, as in the last problem. It shows a clear peak from 15 s to 20 s, with fewer runners on each side.
Answer: four bars. Five to ten groups usually work well; with only 18 values, four or five is enough.
Discussion (0)
Log in to join the discussion.
Loading…