The masses in kilograms of 50 children having a medical check-up were recorded correct to the nearest kilogram. The results are shown in the table. Mass (kg) 10–14 15–19 20–24 25–34 35–59 Frequency 6 12 14 10 8

Mark scheme

Marking points from the official mark scheme (May/June 2018). The mark or mark type is shown in brackets.

1. [1] B1 15-19 (kg) cao kg not necessary; condone 14.5 – 19.5
2. [4] M1 Attempt at fd [f/(attempt at cw)] or scaled freq (may be implied by 4 correct)
3. [4] A1 Correct heights seen on diagram with linear vertical scale from (x, 0)
4. [4] B1 Correct bar widths (1:1:1:2:5) visually no gaps with linear horizontal scale from (9.5,y) and first bar starting at (9.5, y)
5. [4] B1 Histogram, using attempted fds, with labels (mass, kg and fd seen) and at least 3 linearly spaced values on each axis. Horizontal axis must range from at least 9.5 to 59.5 If horizontal axis clearly starts from zero, either a break in the scale must be indicated or the scale must be linear from zero.