4.6 A consumer group has tested ten makes of personal stereo.

The prices and the score (out of 100) awarded to them by a panel of experts the group commissioned to test them, are:

Price (£) 95 69 18 32 27 70 49 35 50 29 Score 74 63 28 33 37 58 38 43 50 31

(a) Plot a scatter diagram to portray the data taking score as the dependent variable.

(b) Find the equation of the line of best fit using simple linear regression.

(c) Plot the line of best fit on the scatter diagram produced for (a).

(d) Use the regression equation from

(c) to predict the score that the panel of experts would award to a personal stereo priced £40.