Scatterplots

The scatter plot shows the relationship between the number of chapters and the total number of pages for several books.  Use the trend line to predict how many chapters would be in a book with 180 pages. 

• 12 chapters

• 15 chapters

• 18 chapters

• 21 chapters

Which statement best describes the relationship shown in this scatter plot?

• Students with a bigger shoe size earn a higher math score

• Students with a smaller show size earn a higher math score

• A student's shoe size has no effect on their math score

• A student with a shoe size of 8 will always earn a score of 80%

Which graph shows a line of best fit for the scatter plot?

• Graph A

• Graph B

• Graph C

• Graph D

Estimate the correlation coefficient for this scatterplot.

• r = 1.2

• r = 0.89

• r = 0

• r = -0.89

Estimate the correlation coefficient for this scatterplot.

• r = -0.9

• r = 1

• r = 0.9

• r = -1

What type of association does this graph have?

• positive 

• negative

• none

• all of the above

As x increases, y decreases.

• no correlation

• negative correlation

• correlation coefficient

• positive correlation

Graph has a slope of 1/2 and a y- intercept of 1.  Write the equation in slope - intercept form

• y = 1x+1/2

• y = 1/2x + 1

Find the slope for the trend line using points (2,2) and (4,3)

• 2

• 1/2

• -2

The linear regression equation for the data is  y = 1.5x + 12.  Interpret the slope of the equation.

• The slope is (0, 1.5).  It means that a pizza with 0 toppings will cost $1.50.

• The slope is 1.5.  It means that it costs $1.50 per topping.

• There are 1.5 toppings.

• There are 1.5 pizzas.