OCR MEI AS Paper 2 Specimen — Question 7

Exam BoardOCR MEI
ModuleAS Paper 2 (AS Paper 2)
SessionSpecimen
TopicMeasures of Location and Spread
TypeIdentify appropriate measure with outliers

7 A farmer has 200 apple trees. She is investigating the masses of the crops of apples from individual trees. She decides to select a sample of these trees and find the mass of the crop for each tree.
  1. Explain how she can select a random sample of 10 different trees from the 200 trees. The masses of the crops from the 10 trees, measured in kg, are recorded as follows.
    \(\begin{array} { l l l l l l l l l l } 23.5 & 27.4 & 26.2 & 29.0 & 25.1 & 27.4 & 26.2 & 28.3 & 38.1 & 24.9 \end{array}\)
  2. For these data find
    • the mean,
    • the sample standard deviation.
    • Show that there is one outlier at the upper end of the data. How should the farmer decide whether to use this outlier in any further analysis of the data?