Unit 6 Day 5 Quiz Part A 4th period

Last updated over 4 years ago
7 questions
4

Residuals are . . .

4

A company’s sales increase by 14.5% each year. This growth is . . .

linear, exponential or power?

4

If America's Biggest Loser contestant weighed 421 lb at the start and lost about 5.2% of their weight each week...

is this linear, exponential or power?

2

To more easily determine the age of a tree (without cutting it down and counting the rings) a forester measured 27 trees of the same species that had been cut down and counted the rings to determine if the ages were correlated to the diameter of the trunk.
The computer output information is shown below, age is in years and diameter is in cm:

Variable Coefficient
Constant -0.9744
Diameter 2.2055

R-Squared: 78.9% S: 5.5764

What is the correlation coefficient of the relationship between the tree diameter in cm and age in years?
Round to three places past the decimal.
Hint: you will need to use a number above and do a calculation.
Another hint: what letter represents the correlation coefficient?

4

To more easily determine the age of a tree (without cutting it down and counting the rings) a forester measured 27 trees of the same species that had been cut down and counted the rings to determine if the ages were correlated to the diameter of the trunk.
The computer output information for a linear regression is shown below, age is in years and diameter is in cm:

Variable Coefficient R-Squared: 78.9% S: 5.5764
Constant -0.9744
Diameter 2.2055

Set up the linear regression equation to predict the age of the tree based on the diameter.
Use 'years' and 'diameter' for the variable names.
Make sure to indicate which variable is being predicted.
Keep all decimal places.
No spaces

4

Use your equation for predicting the age of the tree to calculate the age of a tree that was 29.4 cm in diameter.

Keep all decimal places.

4

If our calculation of the tree's age gave a residual of -5.682, what was the tree's actual age?

Keep all decimal places.