# Question 2:

## Part (i)
35 | B1 | Allow 30 to 40 inclusive

**[1]**

## Part (ii)
$\frac{50 \pm 2}{400} \times 100$ | M1 | NOT $\frac{50\pm2}{450} \times 100$; NOT $\frac{100\pm2}{400\text{ or }450} \times 100$

$= 12\%$ to $13\%$ | A1 | NOT $\frac{350\pm2}{400} \times 100$ (unless sub from 100)

**[2]**

## Part (iii)
e.g. 7.5, 87.5 or 5, 90 or 5–10, 85–90 | B1 | or any values in intervals 5–10 & 85–90; NOT "Because it's cumulative frequency"

"Classes" or "intervals" or "groups" or "mid-points" or "bounds" seen; Data lost | B1 | No raw data given. Not have each data value; Exact values not given or can't be read off; NOT "Because it's a line of best fit"; NOT "Because graph is difficult to read"; NOT "because graph is a curve"; NOT "Cont data has no exact data pts"

**[2]**

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# Question 2 (continued):

## Part (iv)
Median $= 39 \pm 1$ drawn | B1 | or stated; Mark diagram even if contradicts statements

Quartiles $= 25 \pm 1,\ 55 \pm 1$ drawn | B1 | or stated; statements of values in (iv) or (iii)

Ends in ranges 5–10 & 85–90 drawn | B1f | or ft (iii); If no diagram, award max B1B1B1 for statements of med, quartiles & ends

Correct B&W plot $\pm 1$ drawn | B1f | or ft (iii) mark intention (allow unruled lines)

**[4]**

## Part (v)
Stretched out at top end | B1 | Positive skew; Skewed to right (or to higher values); Larger skewness at top; Larger plums more spread than smaller ones; NOT any of below: more large extremes than small extremes; IQR is towards the lower end; skewed to the left; majority below 39; distribution towards lower end

Not symmetrical; More concentrated towards lower end; More values (or data) in lower half of range; Median closer to lowest value; Average towards lower end; More plums have lower masses; Majority of distribution towards lower end; More below 50 (or 45); Upper whisker longer than lower whisker | | Ignore all else; No need for context

**[1]**

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