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 (MEI) A Level Maths 2.2 Data Presentation and Interpretation, covering 2.2.1 Types of data and standard diagrams, 2.2.2 Area in a histogram is proportional to frequency, 2.2.3 Cumulative frequency diagram, 2.2.4 Describe frequency distributions, 2.2.5 Samples and theoretical distributions, 2.2.6 Interpret a scatter diagram, 2.2.7 Distinct sections and outliers in scatter diagrams, 2.2.8 Correlation and causation, 2.2.9 Select or critique data presentation techniques, 2.2.10 Measures of central tendency, 2.2.11 Simple measures of spread, 2.2.12 Variance and standard deviation, 2.2.13 Outliers, 2.2.14 Cleaning data, and 2.2 Data Presentation and Interpretation. Each one has a worked solution and a mark scheme showing where the marks go.