The company Seafield requires contractors to record the number of hours they work each week. A random sample of 38 weeks is taken and the number of hours worked per week by contractor Kiana is summarised in the stem and leaf diagram below. (a) Find the values of $$\(w, x\)$$ and $$\(y\)$$ (3) Kiana is looking for outliers in the data. She decides to classify as outliers any observations greater than $$\[ Q_{3}+1.0 \times\left(Q_{3}-Q_{1}\right) \]$$ (b) Showing your working clearly, identify any outliers that Kiana finds. (2) (c) Draw a box plot for these data in the space provided on the grid opposite. (3) (d) Use the formula $$\[ \text { skewness }=\frac{\left(Q_{3}-Q_{2}\right)-\left(Q_{2}-Q_{1}\right)}{\left(Q_{3}-Q_{1}\right)} \]$$ to find the skewness of these data. Give your answer to 2 significant figures. (2) Kiana's new employer, Landacre, wishes to know the average number of hours per week she worked during her employment at Seafield to help calculate the cost of employing her. (e) Explain why Landacre might prefer to know Kiana's mean, rather than median, number of hours worked per week. (1)

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