A psychologist recorded how long 42 participants took to complete a maze task. The results were grouped as follows.
| Time taken (seconds) | Number of participants |
|---|---|
| 15 to under 25 | 6 |
| 25 to under 35 | 9 |
| 35 to under 45 | 15 |
| 45 to under 55 | 12 |
Calculate, in its lowest terms, the fraction represented by participants who took at least 25 seconds but less than 45 seconds.
173 exam-style questions on OCR GCSE Psychology 7.3 Analysing Research, covering 7.3.1 Types of Data, 7.3.2 Measures of central tendency, 7.3.3 Other descriptive statistics, 7.3.4 Tables, Charts and Graphs, 7.3.5 Reliability, 7.3.6 Validity and effects on validity, and 7.3.7 Sources of bias. Each one has a worked solution and a mark scheme showing where the marks go.