An acoustician conducted an environmental study on noise pollution in a suburban nature reserve. Audio sensors recorded the dominant sound source during various intervals overnight. The recorded frequencies of these sources are summarised in the table below.
| Dominant sound source | Frequency |
|---|---|
| Anthropogenic traffic | 72 |
| Industrial machinery | 41 |
| Biogenic activity | 12 |
Calculate the percentage of recorded intervals where the dominant sound source was identified as neither anthropogenic traffic nor industrial machinery. Show your working.
513 exam-style questions on OCR A Level Psychology Data recording, analysis and presentation. Each one has a worked solution and a mark scheme showing where the marks go.