In an investigation to determine the effectiveness of a plant hormone spray, abscisic acid (ABA), in reducing water loss, ten potted plants were sprayed with water (Control) and another ten plants of the same species were sprayed with ABA (Treated). The percentage decrease in the mass of each pot over 24 hours was recorded. The results are shown in the table below: PlantControl water loss (%)ABA Treated water loss (%)18.45.228.15.138.35.248.50.458.25.068.64.978.45.288.35.198.55.0108.25.2Average8.3?\begin{array}{c|c|c} \text{Plant} & \text{Control water loss (\%)} & \text{ABA Treated water loss (\%)} \\\hline 1 & 8.4 & 5.2 \\ 2 & 8.1 & 5.1 \\ 3 & 8.3 & 5.2 \\ 4 & 8.5 & 0.4 \\ 5 & 8.2 & 5.0 \\ 6 & 8.6 & 4.9 \\ 7 & 8.4 & 5.2 \\ 8 & 8.3 & 5.1 \\ 9 & 8.5 & 5.0 \\ 10 & 8.2 & 5.2 \\\hline \textbf{Average} & \textbf{8.3} & \textbf{?} \end{array}Plant12345678910AverageControl water loss (%)8.48.18.38.58.28.68.48.38.58.28.3ABA Treated water loss (%)5.25.15.20.45.04.95.25.15.05.2?
The results for the ABA Treated plants contain one anomalous result. Identify the anomalous result and calculate the correct average percentage decrease in mass for the ABA Treated plants. Show your working.
26 exam-style questions on Edexcel IGCSE Biology Co-ordination and response. Each one has a worked solution and a mark scheme showing where the marks go.