GCSE · Data representation
Time seriesExam-style questions
Measurements plotted against time and joined in order — why joining is legitimate here but not on a scatter graph, how to describe a trend so it earns the mark, how to spot seasonal variation and use it to predict the next quarter, and why predicting far beyond the data is worthless.
11 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try
- 1Sam sells caravans. The time-series graph shows the number of caravans he sold in each quarter of 2024 and 2025.
Quarter 1 on the graph is the first quarter of 2024 and quarter 5 is the first quarter of 2025.(a) Work out the total number of caravans Sam sold in 2025.
(b) Work out the percentage increase in the total number of caravans sold from 2024 to 2025.
Give your answer correct to 1 decimal place.
(c) Sam also draws a scatter graph showing the age and the price of each of 20 second-hand caravans. He joins the points on that scatter graph with straight lines, as he did on the time-series graph above.
Explain why joining the points is sensible on the time-series graph but not on the scatter graph.Level 5 · 7 marksTry it - 2A firm hires out camper vans. The time-series graph shows the number of camper vans it hired out in each quarter from 2023 to 2025.
Quarter 1 on the graph is the first quarter of 2023, quarter 5 is the first quarter of 2024 and quarter 9 is the first quarter of 2025.(a) Work out the increase in the number of camper vans hired out in quarter 2 from 2023 to 2025.
(b) Adele says: "In each year the firm hires out about four times as many camper vans in quarter 3 as in quarter 1, so that will always be true."
Comment on Adele's statement. You must refer to figures from the graph.
(c) Adele uses the graph to predict that the firm will hire out 28 camper vans in quarter 3 of 2040.
Explain why this prediction is unreliable.Level 5 · 5 marksTry it