Scatter Graphs

Worksheet Answers

Worksheet 1: Programme Questions

1. Number of months as a taxi driver
2. Positive (high or strong)
3. Line of best fit
4. VO2 Max
5. Minutes
6. Negative
7. About 4 hours
8. Jamie drew his line through the origin
9. Blue
10. There was no (zero) correlation

Worksheet 2: Tick or Trash

Question 1

Student A is correct. Student B has tried to give reasons for the link rather than describing the nature of the relationship.

Question 2

Student B is correct. Student A has misread the scale for hours of sunshine, but the line is acceptable.

Note: the scales do not both start at 0 and each square's side represents different units in the two directions.

Worksheet 3: Exam Practice Questions (Edexcel)

This is a selection of past exam questions from Edexcel, targeted at the middle ability range. You can use the sequence as it stands or select individual questions to suit your needs.

Below is the mark scheme for each question, which may help you to see how marks are allocated and what the examiner is especially looking for. The mark schemes use the following abbreviations:

oe	or equivalent
cao	correct answer only
ft	follow-through marks
dep	dependent
indep	independent
M	method marks
A	accuracy marks
B	benefit-of-doubt mark
SC	special case

Question 1

(a) Line of best fit
(b) i) Distance = 5.2m -> 1.685m
ii) Height = 1.83m -> 5.6m

Notes:
(a) B2 if fully within overlay guides
B1 cao if no less than half within the guides

(b) i) B1 ± square (ft) dep on at least B1 in (a)
ii) B1 ± square (ft) dep on at least B1 in (a)

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Question 2

(a) Points correctly plotted
(b) Negative

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Question 3

(a) Line of best fit
(b) Draw line 'amount = 10.4' on graph or state use of amount = 10.4; price about £16.50

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Question 4

(a) Line of best fit (only straight line)
(b) i) Accept 136-140 pages
ii) Accept 216-220g

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Question 5

(a) Scatter graph
(b) Negative
(c) Line of best fit
(d) i) 35 units ->
ii) 7ºC ->

Notes:
(a) B2 for 4 points correct ± half a square
B1 for 2 points correct ± half a square
(b) B1 cao (do not accept a description of the relationship)
(c) B2
(d) i) B1 ft ± half a square (dep on a single overall line)
ii) B1 ft ± half a square (dep on a single overall line)

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Question 6

(a) Bigger engine size, shorter times, faster (oe)
(b) Line of best fit
(c) 16 seconds
(d)
(e)

Notes:
(a) B1 cao
(b) B1 within straight line (extensions) on overlay
(c) B1 ft on line (dep on a line given) ± 0.4
(d) B1 cao accept 0.55, 0.56 oe or better
(e) B1 cao accept 0.22 or better