A-LevelMathematicsProbability and statistics9709/63 · Oct/Nov 2017 · Q59 Marks

The number of Olympic medals won in the 2012 Olympic Games by the top 27 countries is shown below. 104 88 82 65 44 38 35 34 28 28 18 18 17 17 14 13 13 12 12 10 10 10 9 6 5 2 2

(i)Draw a stem-and-leaf diagram to illustrate the data.[4]
(ii)Find the median and quartiles and draw a box-and-whisker plot on the grid.[5]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2017). The mark or mark type is shown in brackets.

[B1] Stem, digits 5, 7, 9 can be missing here, can be upside down
[B1] All leaves in correct order increasing from stem, (5, 7 and 9 can be missing), condone commas
[B1] Reasonable shape, requires all values of the stem, only one line for each stem and leaves must be lined up. Can be upside down or sideways. No commas. Condone one 'leaf" error.
[B1] Correct key must state 'medals' or have 'medals' in leaf heading or title
[B1] Median correct
[B1] LQ and UQ correct
[B1] Uniform scale from 2 to 104 (need 3 identified points min) and label including medals (can be in title)
[B1 FT] Correct box med and quartiles on diagram, FT their values
[B1] Correct end-whiskers from ends of box but not through box

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