Unit 4 Test Retake

What type of correlation is shown in this plot?

• Positive
• Negative
• No Correlation

Estimate the correlation coefficient for this scatterplot.

• r = 1.2

• r = 0.89

• r = 0

• r = -0.89

r=0.3

• Strong positive

• Weak positive

• Strong negative

• Weak negative

A restaurant sells pizza for the prices in the data table. Calculate the linear regression equation of the data.

• y = 1.5x + 12

• y = 12x + 1.5

• y = 0.67x - 8

• y = -8x + 0.67

The linear regression equation is y = 61.93x - 1.79.  Use the equation to predict how far this person will travel after 10 hours of driving.

• 10 miles
• 617.5 miles
• 0.19 miles
• 500 miles

The annual profits for a company are given in the following table, where x represents the number of years since 1992, and y represents the profit in thousands of dollars. Write the linear regression equation that represents this set of data, rounding all coefficients to the nearest hundredth. Using this equation, estimate the year in which the profits would reach 378 thousand dollars.

• 2029

• 2014

• 2003

• 8753

A perfect negative correlation has a correlation coefficient of ____. 

• 1
• -1
• 0

Number of steps taken per day and number of kilometers walked per day.  $r=.92$  

• strong positive

• strong negative

• weak positive

• weak negative

Which of the following could be the equation of the trend line for this graph?

• $y=10x\ -\ 15$

• $y=-3x+12$

• $y=\frac{1}{2}x+11$

• $y=-\frac{4}{3}x$

• There is no trend line because there is no association