Higher November 2018 Paper 4 Q12

OCRHigherCurrent spec5 marksHistograms

12 30 students completed a puzzle and their times were recorded.
All of the students completed the puzzle in less than 50 seconds.
The histogram shows information about some of their times.

Histogram of time taken (seconds) against frequency density: bars 10–25 at 0.8, 25–35 at 0.9 and 35–50 at 0.2; nothing drawn from 0 to 10

Complete the histogram for those completing the puzzle in less than 10 seconds. [5]

Mark scheme

Answer	Marks	Part marks and guidance
correct bar width and ‘height’ of 0.6	5	M2 for 15 × 0.8 + 10 × 0.9 + 15 × 0.2 or better e.g. 12 + 9 + 3 or 24 or M1 for two correct frequencies calculated from 12, 9 and 3 AND M1 for 30 – their 24 soi 6 M1 for their 6 ÷ 10 soi 0.6