Scatter Graphs worksheet
8 GCSE practice questions with answers, free to print. Every sheet is generated, so you can make a fresh one whenever you need it.
-
2 marks
A shop recorded the highest temperature and the number of bottles of cold water sold on each of nine days.
(a)Describe the correlation shown by the scatter graph.
(b)Write down what this tells you about the number of bottles of cold water the shop sold.
-
2 marks
The scatter graph shows the height and the mass of each of the nine students in Dev's tutor group.
A line of best fit has been drawn.
(a)Use the line of best fit to estimate the mass of a student of height 174 cm.
(b)Use the line of best fit to estimate the height of a student of mass 53 kg.
-
3 marks
Nine students recorded how long they spent revising for a test and the mark they scored. The test was marked out of \(100\).
The scatter graph shows the results, with a line of best fit.
(a)Use the line of best fit to estimate the mark of a student who revised for 11 hours.
(b)Reuben says the graph can be used to estimate the mark of a student who revised for 30 hours.
Explain why he would not be able to rely on that estimate.
-
2 marks
Farrah collected data on the number of ice creams sold and the number of people treated for sunburn for 90 days.
She drew a scatter graph and found strong positive correlation.
Farrah concluded that selling ice creams causes sunburn.
-
3 marks
A dealer recorded the age and the value of nine second-hand Halcyon cars.
The scatter graph shows the results, with a line of best fit.
(a)Work out the gradient of the line of best fit.
(b)Write down what the gradient tells you about the value of this model of car.
-
2 marks
A shop recorded the highest temperature and the number of ice creams sold on each of nine days.
(a)Describe the correlation shown by the scatter graph.
(b)Write down what this tells you about the number of ice creams the shop sold.
-
2 marks
The scatter graph shows the height and the mass of each of the nine students in Idris's tutor group.
A line of best fit has been drawn.
(a)Use the line of best fit to estimate the mass of a student of height 174 cm.
(b)Use the line of best fit to estimate the height of a student of mass 57 kg.
-
3 marks
Nine students recorded how long they spent revising for a test and the mark they scored. The test was marked out of \(100\).
The scatter graph shows the results, with a line of best fit.
(a)Use the line of best fit to estimate the mark of a student who revised for 13 hours.
(b)Priya says the graph can be used to estimate the mark of a student who revised for 30 hours.
Explain why she would not be able to rely on that estimate.
Answers
-
(a) Positive correlation
(b) The warmer the day, the more bottles of cold water the shop sold -
(a) \(59\ \text{kg}\)
(b) \(162\ \text{cm}\) -
(a) \(52\)
(b) 30 hours is far outside the range of the data (2 hours to 18 hours), so there is no evidence that the pattern carries on that far; the line would give a mark of 128, which is impossible out of 100. - Farrah is wrong to conclude that: correlation does not show that one thing causes the other. Both are affected by how hot and sunny the weather was.
-
(a) \(-800\)
(b) The value falls by about £800 for each extra year of age. -
(a) Positive correlation
(b) The warmer the day, the more ice creams the shop sold -
(a) \(63\ \text{kg}\)
(b) \(162\ \text{cm}\) -
(a) \(60\)
(b) 30 hours is far outside the range of the data (2 hours to 18 hours), so there is no evidence that the pattern carries on that far; the line would give a mark of 128, which is impossible out of 100.