1. The sales people at Archway's Car Depot earn commission based on how many and what types of cars they sell. The table below shows the profit made by ten Archway's Car Depot salespeople after selling x cars.
Number of cars sold Profit(£)
1 3,500
2 13,000
3 10,000
3 5,700
4 16,500
5 4,000
6 12,550
7 18,000
7 14,000
9 21,000
a) Create a scatterplot that represents the above data.
b) Find the equation of the regression line. Add this line on your scatterplot.
c) For the regression the y-intercept is__________. In your own words, explain what the yintercept value represents in this scenario.
d) The slope is___________. In your own words, explain what the slope represents in this scenario.
e) A salesman makes a profit of £8,550. Using your regression line, estimate the number of cars the salesman sold. Plot the point on your graph.
f) Describe the relationship between the number of cars sold and the profit salespeople make.
g) A salesperson makes £78,000 after selling three cars. Does this fit the trend shown in your graph? Why or why not?
2. Tourists seeking holiday accommodation in a self-catering complex in the resort of Barbados can make either a one or two week booking. The manager of the complex has produced the following table to show the bookings she received last season:
Type of Booking
Tourist's home country One week Two week
France 13 44
Germany 29 36
Holland 17 21
Ireland 8 5
Required:
a) Produce a simple bar chart to show the total number of bookings by home country.
b) Produce a component bar chart to show the number of bookings by home country and type of booking.
c) Produce a clustered bar chart to show the number of bookings by home country and type of booking.
d) Interpret your results
3. Twenty five shoppers were asked about the number of credit cards they carried with them. The table included below shows the data collected.
Shopper Number of cards carried
1 2
2 5
3 2
4 0
5 4
6 3
7 0
8 1
9 2
10 7
11 2
12 4
13 1
14 3
15 9
16 4
17 1
18 4
19 1
20 5
21 5
22 2
23 3
24 1
25 2
Required:
a) Determine the mode and median of this distribution.
b) Calculate the mean of the distribution and compare it to the mode and median. What can you conclude about the shape of the distribution?
c) Draw a bar chart to represent the distribution and confirm your conclusions.
d) Find the lower and upper quartiles of the data and use them to work out the semi-interquartile range.
4. A garage starts a breakdown service that offers assistance in mornings, afternoons and evenings. The number of call-outs during the first three days of the service are presented in the table below:
Morning Afternoon Evening
Day 1 12 6 9
Day 2 15 9 12
Day 3 18 9 15
Required:
a) Plot the above data series over time.
b) Work out three-point moving averages for the series and plot them on your graph.