The times 12 athletes took to run 400m is summarised in the table below.
| Athlete | A | B | C | D | E | F | G | H | A | I | J | K |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Time (s) | 45.2 | 46.9 | 46.1 | 46.2 | 45.4 | 45.1 | 47.8 | 45.4 | 45.5 | 46.1 | 46.4 | 45.7 |
Find the mean time taken.
Find the standard deviation for these times.
Find the median, upper and lower quartiles of these data.
121 exam-style questions on OCR A Level Maths 2.2 Data Presentation and Interpretation, covering 2.2.1 Tables and diagrams for single variable data, 2.2.2 Area in a histogram, 2.2.3 Scatter diagrams and regression lines, 2.2.4 Informal interpretation of correlation, 2.2.5 Correlation and causation, 2.2.6 Measures of average and spread, 2.2.7 Calculations of mean and standard deviation, 2.2.8 Outliers, 2.2.9 Selecting or critiquing data presentation, and 2.2.10 Cleaning data. Each one has a worked solution and a mark scheme showing where the marks go.