Leaving gaps between histogram bars H
"The Gap Problem"
The Mistake in Action
Student draws a histogram with gaps between each bar, like a bar chart.
Why It Happens
Bar charts for categorical data have gaps; students apply the same style to histograms.
The Fix
Histograms represent continuous data — there are no gaps between classes.
- Bar charts: Discrete/categorical data → gaps between bars
- Histograms: Continuous data → no gaps between bars
The bars in a histogram touch because one class ends exactly where the next begins (e.g., 10 ≤ x < 20 is followed by 20 ≤ x < 30).
If there genuinely is a gap in the data (e.g., no values between 30 and 50), the histogram simply has no bar in that region — but adjacent classes still touch.
Spot the Mistake
Can you identify where this student went wrong?
Drawing a histogram
with gaps between bars
Click on the line that contains the error.
Related Topics
Learn more about the underlying maths: