# A student is investigating how the mass of sugar dissolved in water affects the time taken for the solution to reach a certain temperature when heated. The student plans to repeat each measurement three times and calculate a mean. Explain why repeating measurements and calculating a mean improves the quality of the results.

> OCR GCSE Physics A: Gateway Science (J249) — P9 Practical skills · Explain · 4 marks

## Mark scheme (4 marks)

1. Repeating measurements allows anomalous results / outliers to be identified
2. Anomalous results can be discarded / not included in the mean
3. Calculating a mean reduces the effect of random errors
4. This makes the result more reliable / increases reliability

## Key terms

- [mean](https://www.gradenine.co.uk/glossary/mean)

## Related

- [Revision notes for OCR GCSE Physics A: Gateway Science (J249)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-student-is-investigating-how-the-7a1d6f9b) · Published by Druglandscape Ltd.