# Question: the following data represent the approximate retail price in ...

###### Question details

The following data represent the approximate retail price (in $) and water usage per year (in $) of nine washing machine displayed at the local shopping mall:

Brand Price ($)X, Water Usage per year($),Y

A 1,600 73

B 1,200 73

C 1,550 78

D 1,350 85

E 1,700 93

F 1,700 95

G 1,500 96

H 1,400 94

I 1,200 95

a) Construct a scatter plot. [3 marks]

b) (i) Find the regression equation for predicting the water usage per year. [6 marks]

(ii) Interpret the meaning of the slope in this question. [2 marks]

(iii) Predict the average water usage per year for a washing machine priced at $1500. [2 marks]

(iv) Predict the average water usage per year for a washing machine price at $1900. [2 marks]

c) (i) Compute the correlation coefficient for this regression model. [3 marks]

(ii) Describe the relationship between water usage per year and the price of washing machine. [3 marks]

d) Compute the mean and standard deviation of the water usage per year for the 4 most expensive brands. [4 marks]