The sterplot shows the relationship between x and y . A line of best fit is also shown. The sterplot

Question

The sterplot shows the relationship between $x$ and $y$ . A line of best fit is also shown.

Which of the following is closest to the slope of the line of best fit shown?

Accepted Answer

Choice C is correct. It's given that the sterplot shows the relationship between two variables, x and y , and a line of best fit is shown. For the line of best fit shown, for each increase in the value of x by 1 , the corresponding value of y increases by a constant rate. It follows that the relationship between the variables x and y has a positive linear trend. A line in the xy -plane that passes through the points a , b and c , d has a slope of d - b c - a . The line of best fit shown passes approximately through the points 0 , 0.25 and 4 , 2 . It follows that the slope of this line is approximately 2 - 0.25 4 - 0 , which is equivalent to 0.4375 . Therefore, of the given choices, 0.44 is closest to the slope of the line of best fit shown. Choice A is incorrect. This is the slope of a line of best fit for a relationship between x and y that has a negative, rather than a positive, linear trend. Choice B is incorrect. This is the slope of a line of best fit for a relationship between x and y that has a negative, rather than a positive, linear trend. Choice D is incorrect and may result from conceptual or calculation errors.

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