EDEXCEL GCSE MATHS · FOUNDATION & HIGHER
Exam Practice: Scatter Graphs
Scatter graphs · Interpreting and representing data · Lesson 3 of 6 · 6 marks · 15 minutes
Name Date
Answer all questions.
Question 1 CALCULATOR [3 marks]
The scatter graph shows the midday temperature and the number of hot chocolates sold by a café on 12 days. (a) What type of correlation does the graph show? (b) One of the points is an outlier. Write down its coordinates. (c) Describe the relationship between the temperature and the number of hot chocolates sold.
Question 2 CALCULATOR [2 marks]
Data from one summer shows positive correlation between ice cream sales and the number of people with sunburn. Jo says, "Eating ice cream causes sunburn." Is Jo correct? Explain your answer.
Question 3 CALCULATOR [1 mark]
Which of these pairs is most likely to show negative correlation? A: a person's height and their arm span. B: the age of a car and its value. C: a person's house number and their age.
Answers
Check your answer only once you have written one.
Question 1 [3 marks]
(a) Negative correlation. (b) (22, 60). (c) As the temperature increases, the number of hot chocolates sold decreases.
▸ (a) Negative B1
▸ (b) (22, 60) B1
▸ (c) A statement in context, e.g. the warmer it is, the fewer hot chocolates are sold C1
Question 2 [2 marks]
No. Correlation does not show that one causes the other. Both ice cream sales and sunburn increase because of a third factor - hot, sunny weather.
▸ No, with a statement that correlation does not prove causation C1
▸ A third factor identified, e.g. hot or sunny weather C1
Question 3 [1 mark]
B - as a car gets older, its value goes down.
▸ B B1