GCSE · Histograms

Histograms & frequency densityExam-style questions

Why a histogram with unequal class widths cannot use frequency as the bar height, and how the rule "area = frequency" fixes it: height = frequency ÷ class width. Drawing the bars, reading a frequency back off a bar as density × width, and why the axis must say "Frequency density".

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10 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try

DifficultyAllLevel 2Level 3Level 4Level 5
  1. 1
    The table shows information about the masses, mm kilograms, of 70 suitcases checked in at an airport desk.
    Mass, mm (kg)Frequency
    0<m≤200 < m \le 2036
    20<m≤3020 < m \le 3022
    30<m≤6030 < m \le 6012
    (a) Work out the frequency density of each class.

    (b) Ravi says, "The class 0<m≤200 < m \le 20 must have the tallest bar on the histogram, because it has the largest frequency."

    Is Ravi correct? Explain your answer.
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