Linear Association with R Value

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

• y = 3/2x + 12

• y = 12x + 1.5

• y = 2/3x - 8

• y = -8x + 0.67

• y = 2/3x + 12

Tags

Statistics

Line of Best Fit

Which sentence(s) describes the relationship shown on this scatterplot?

• As the temperature decreases, the visitors increase.

• As the temperature increases, the number of visitors increases.

• As the visitors increase, the temperature decreases.

• No correlation between temperature and visitors

• There is a positive correlation between temperature and visitors

Tags

Statistics

Scatter Plots

The correlation coefficient, r is used to determine

• y values given values of x.

• x values given values of y.

• the strength and direction of relationship between x and y.

• none of these.

A perfect positive correlation has a correlation coefficient of ____. 

• 1

• -1

• 0

Which graph represents data that has a correlation coefficient close to -1?

• 
• 
• 
• 

Coefficient of correlation lies between

• 0 and +1

• 0 and -1

• -1 and +1

• -5 and +5

Answer explanation

The value of r must be between -1 and +1

Estimate the correlation coefficient.

• r=0

• r=-1

• r=1

• r=2

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

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 linear regression equation is y = 61.93x - 1.79.  According to the model, the slope can be interpreted as:

• After 0 hours of driving, they went 61.93 miles.

• They drove at a speed of 61.93 miles per hour.

• They drove 61.93 miles total.

• They drove 61.93 hours total.