Cambridge IGCSE Maths (0580) · Topic 9: Statistics · 9.5
Scatter Diagrams questions with worked answers for Cambridge IGCSE Mathematics (0580). Each question says whether it is Core or Extended and whether it is for a calculator or non-calculator paper. Try each one before you open the answer.
Summarised in our own words: check the exact wording in the official 0580 syllabus.
For everyone: Core students (Papers 1 and 3) and Extended students (Papers 2 and 4).
What type of correlation would you expect between
(a) daily temperature and ice-cream sales
(b) the age of a car and its value
(c) a person's shoe size and the number of their house?
Answer: (a) positive (b) negative (c) no correlation
What type of correlation would you expect between the heights of adults and their shoe sizes?
Answer: positive correlation
The table shows the hours six students revised and their test scores.
Describe the correlation and what it shows.
| Hours revised | 1 | 2 | 3 | 4 | 5 | 6 |
|---|---|---|---|---|---|---|
| Score | 35 | 42 | 50 | 55 | 63 | 70 |
Answer: Positive correlation: more revision, higher scores
A line of best fit for some data has the equation \(y = 7.5x + 25\), where \(x\) is hours revised and \(y\) is the test score.
Estimate the score of a student who revised for \(4.5\) hours.
Answer: \(58.75\) (about \(59\))
The data in a scatter diagram run from \(1\) to \(6\) hours of revision. Explain why using the line of best fit to estimate the score for \(15\) hours of revision may not be reliable.
Answer: \(15\) hours is outside the range of the data, so the estimate is extrapolation and may not be reliable
The table shows six points plotted on a scatter diagram. Five of them lie close to a straight line.
Which point is the outlier?
| x | 1 | 2 | 3 | 4 | 5 | 6 |
|---|---|---|---|---|---|---|
| y | 8 | 11 | 13 | 30 | 19 | 22 |
Answer: \((4, 30)\)
In a town, the number of ice creams sold each day and the number of people with sunburn each day show strong positive correlation. Does this mean that eating ice cream causes sunburn? Explain your answer.
Answer: No: both are linked to hot, sunny weather; correlation does not prove cause
A line of best fit should pass through the mean point \((\bar{x}, \bar{y})\).
Find the mean point for the data in the table.
| x | 1 | 2 | 3 | 4 | 5 | 6 |
|---|---|---|---|---|---|---|
| y | 35 | 42 | 50 | 55 | 63 | 70 |
Answer: \((3.5, 52.5)\)
The table shows the hours of television watched in a week and the test scores of 7 students.
\[\begin{array}{c|ccccccc} \text{TV (hours)} & 1 & 2 & 3 & 4 & 5 & 6 & 7 \\ \hline \text{Score} & 78 & 74 & 65 & 62 & 55 & 50 & 46 \end{array}\]
(a) Describe the correlation.
(b) A line of best fit is drawn by eye. Use it to estimate the score of a student who watched 4.5 hours of television.
Answer: (a) negative correlation (b) about 58 (55 to 62)
Every question on this page is original, written for IGCSE Math Revision rather than taken from Cambridge papers, and each answer was re-solved independently before publishing. Questions with a mark scheme come from our 0580 practice bank (M method, A accuracy, B independent marks).
Scatter Diagrams is on both tiers (syllabus 9.5), so it can come up on Core Papers 1 (non-calculator) and 3 (calculator), and Extended Papers 2 (non-calculator) and 4 (calculator). Extended candidates also need the Extended parts listed on this page. Half of each tier's marks are on a non-calculator paper, so practise the non-calculator questions without one.
No. Every question here was written for IGCSE Math Revision in the style of the 0580 papers, and each answer was checked independently before publishing. For real exam practice, use the Cambridge past papers linked from our 0580 past papers page.
In the 0580 practice for topic 9 (Statistics), where every question is marked and tagged Core or Extended. Practice is part of the IGCSE plan, with a free preview; the questions on this page are free.
IGCSE Math Revision