Reach for the Star

Statistical graphs pathway · Optional extension

L078 · Allow 10–15 minutes for learners ready to move on. Answers are available after an attempt.

Stretch

A histogram class 10–14 has frequency 20 and width 4; class 14–24 has frequency 30 and width 10. Compare densities.

Reveal a worked check after attempting

Densities 5 and 3, so the narrower class has taller bar despite lower frequency.

Deep challenge

Why must a histogram use area rather than bar height for frequency when widths differ?

Reveal a worked check after attempting

Frequency density=frequency/width, so area=width×density=frequency.

Recall & Review: feedback and extension integration

Lesson L078: Statistical graphs pathway

Objective: Select and interpret statistical graphs appropriate to the tier.

60-minute structure: 0-7 Connect & Check; 7-14 Share; 14-25 Present/model; 25-44 Apply route choice/practice; 44-52 independent exam-style check; 52-60 Recall & Review, WWW/EBI and next step.

What Went Well (WWW)

I read or constructed the graph accurately, used the scale and axes correctly and linked the relevant gradient, intercept, shape or trend to my conclusion.

Even Better If (EBI)

I will label units and scale clearly, show the calculation or graphical evidence I used and check that the interpretation fits the context.

Stretch and deep challenge

Stretch: A histogram class 10–14 has frequency 20 and width 4; class 14–24 has frequency 30 and width 10. Compare densities.

Deep challenge: Why must a histogram use area rather than bar height for frequency when widths differ?