Handling Data 6
4 marks · HardThe histogram shows the times taken by 60 students to finish a computer game.
Calculate the total number of students who finished the game in more than 10 minutes but no more than 25 minutes.
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.
Show answer
36 (±1)
Common mistakes: Calculating class width incorrectly; Leaving out bounds, using wrong group
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Marking points
M1 · 1 mark · Identifies correct class widths for 10–15 (5), 15–25 (10)
M2 · 1 mark · Applies frequency formula for each relevant group
A1 · 1 mark · Correct frequencies: (2.4 × 5 = 12), (1.8 × 10 = 18)
A2 · 1 mark · Total frequency added correctly: 12 + 18 = 30. (Award ft if error in one group, sum of their two values). (follow-through)
Worked solution
Relevant groups are 10–15 minutes and 15–25 minutes.
Total frequency = 12 + 18 = 30 students.