A blood donation centre used an automated cell counter to analyse exactly 1 mm3 of blood from each of five donors.
| Donor | Red blood cells detected |
|---|---|
| A | 4 700 000 |
| B | 4 900 000 |
| C | 5 200 000 |
| D | 5 500 000 |
| E | 5 700 000 |
Use the five readings to calculate the arithmetic mean for the donor group.
304 exam-style questions on AQA GCSE Biology 2.2 Animal tissues, organs and organ systems, covering 2.2.1 The human digestive system, 2.2.2 The heart and blood vessels, 2.2.3 Blood, 2.2.4 Coronary heart disease: a non-communicable disease, 2.2.5 Health issues, 2.2.6 The effect of lifestyle on some non-communicable diseases, and 2.2.7 Cancer. Each one has a worked solution and a mark scheme showing where the marks go.