Frequency Density and Histograms
Ages 16–18Difficulty adapts to you
Frequency Density and Histograms
For a histogram, frequency density = frequency ÷ class width. The area of each bar represents frequency, so unequal intervals need different bar heights. Use continuous class boundaries when measurements are grouped into intervals.
Your goals
- ✓You can represent continuous grouped data correctly when class widths are unequal.
- ✓You can use Frequency Density and Histograms, model correctly.
- ✓You can use the definitions, units, assumptions, and examples to check your answer.
Words to know
- Frequency Density and Histograms:
- Represent continuous grouped data correctly when class widths are unequal.
- model:
- A rule or representation used to describe a situation and make a prediction.
Examples
- 1A class of width 5 with frequency 20 has density 20 ÷ 5 = 4; a class of width 10 with frequency 30 has density 3.
- 2Equal-width classes can be compared by frequency, but unequal-width classes must be compared by bar area or density.
Check these
- • Do not skip the meaning of a term or give a result without explaining what it means.
- • Keep every number, symbol, label, and unit in its correct place.
- • Show enough working to check how you reached your answer.
Helpful habits
- • Read the whole question before choosing what to do.
- • Show one clear step at a time and check each step.
- • If you are stuck, draw a model, try smaller numbers, or revisit the example.
Now try your own
Create your own frequency density and histograms example, solve it, and explain how you checked it.
Spark
Creativity & Innovation“Make up a story about the numbers you see.”