Math 1 Unit 3 Practice

Which graph most clearly shows a negative correlation between the x- and y-values?

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Tags

CCSS.HSS.ID.B.6

The linear regression equation for a data set is y = −1.2x + 23.5, where y represents the number of balloons sold by a party store each week and x represents the week number. Use the equation to predict the number of balloons the store will sell during week 8. Round to the nearest whole number.

• 14

• 33

• 73

• 96

Tags

CCSS.8.EE.C.8C

Which correlation coefficient is most accurate for this data set?

• r = −0.3

• r = −0.9

• r = 0.7

• r = 0.9

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.8

CCSS.HSS.ID.C.9

What should be true in order for a scatter plot to show that a linear fit may be appropriate for a data set?

• The points should form an upward curve.

• The points should be scattered randomly.

• The points should appear to lie generally along a line.

• The points should form one line above the x-axis and another below it.

Tags

CCSS.8.F.A.3

The linear regression equation for a data set is y = 1.6x−4.1. The actual value at x=3 is 0.9. What is the residual value at x=3?

Hint: Find YOUR value at x=3.

Residual = Actual−Predicted

• 0.1

• 0.2

• 0.7

• 0.9

The linear regression equation for a data set is y=−2.8x+70.8, where y is the temperature in degrees Fahrenheit, and x is the number of hours since 8 a.m. What does the slope of the equation represent?

• For each hour that goes by, the temperature decreases 2.8 degrees Fahrenheit.

• For each hour that goes by, the temperature increases 2.8 degrees Fahrenheit.

• For each hour that goes by, the temperature decreases 70.8 degrees Fahrenheit.

• For each hour that goes by, the temperature increases 70.8 degrees Fahrenheit.

Tags

CCSS.HSF.LE.B.5

Which scatter plot is most likely to have a correlation coefficient of r = −0.5?

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Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.8

The linear regression equation for a data set is y=3.2x−1.2.

The actual value at x=4 is 14. What is the residual value at x=4?

Hint: Find YOUR value at x=4.

Residual = Actual - Predicted

• 2.4

• 8.0

• 11.6

• 12.8

Tags

CCSS.8.EE.C.8C

What is the correlation coefficient for the data (0, 3), (1, 2), (2, 0)?

• 0.54

• 0.93

• −0.67

• −0.98

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.8

What does a correlation coefficient of r = −0.01 imply about the graph of a data set?

Select all that apply.

• Generally, the slope is positive.

• Generally, the slope is negative.

• A linear model is a good fit for the data

• A linear model is not a good fit for the data.

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.8