Handling Data 6
2 marks · EasyA histogram displays the time (in minutes) customers spend in a shop. The bar for 0–10 minutes has a frequency density of 3, and the bar for 10–30 minutes has a frequency density of 2.
Which interval contains more customers? Explain your answer.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
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10–30 minutes, because frequency = frequency density × class width, and its area is larger.
Also accept: 10–30 minutes, since 2 × 20 = 40 customers, which is more than 0–10 minutes (3 × 10 = 30).; 10–30 minutes interval has more customers because the frequency is 40 while the other is 30.; 10–30 minutes, as its area (frequency) is bigger.
Common mistakes: 0–10 minutes; answers only based on frequency density not area
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Marking points
M1 · 1 mark · Correctly calculates at least one frequency as frequency density × class width.
B1 · 1 mark · Gives the correct interval (10–30 minutes) with a suitable explanation.
Worked solution
For 0–10 minutes: frequency = 3 × 10 = 30.
For 10–30 minutes: frequency = 2 × 20 = 40.
So, the 10–30 minutes interval contains more customers.