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0580/42 May/Jun 2026, Question 19: Estimating the Mean for Grouped Data

Cambridge IGCSE Mathematics 0580 · Paper 42 (Extended) · Calculator · 7 marks

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The question, in short

From a grouped frequency table of 40 customers' shopping times, estimate the mean and complete a frequency density histogram.

Summarised in our own words. Use the official paper for the exact wording and the diagram.

Part (a) · 4 marks

Calculate an estimated mean shopping time from the grouped frequency table with 40 customers.

  1. 1Midpoints: 2.5, 7.5, 15, 30
  2. 2Σft = 7.5 + 135 + 195 + 180 = 517.5
  3. 3Mean = 517.5 ÷ 40 = 12.9375 minutes

Answer12.9375

Part (b) · 3 marks

Complete the histogram using the frequency table, with frequency density on the vertical axis and time on the horizontal axis.

  1. 1Frequency density = frequency ÷ class width
  2. 218 ÷ 5 = 3.6, 13 ÷ 10 = 1.3, 6 ÷ 20 = 0.3
  3. 3Draw bars from 5 to 10 at 3.6, 10 to 20 at 1.3, 20 to 40 at 0.3

AnswerCorrect histogram: bars of height 3.6 (5 < t ≤ 10), 1.3 (10 < t ≤ 20), 0.3 (20 < t ≤ 40)

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Also searched as: 0580/42/M/J/26 · 0580_s26_qp_42 · 0580 s26 42 · question 19.
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