Question

Lots of people use breakfast cereal as a daily source of fiber, and these cereals also contain the mineral potassium. Suppose a linear model was made to predict a cereal's potassium content using its fiber content, and suppose the model had intercept 37 and slope 25. For a cereal having 255 milligrams of potassium and 9 grams of fiber, what is the residual (in mg)?

Answer 1

The residual is of 7 mg.

Explanation:

Linear model:

A linear model has the following format:

`y = mx + b`

In which m is the slope and b is the intercept.

Suppose the model had intercept 37 and slope 25.

This means that
`b = 37, m = 25`

So

`y = 25x + 37`

9 grams of fiber

This means that
`x = 9`. So

`y = 25(9) + 37 = 262`

255 milligrams of potassium. What is the residual (in mg)?

Expected subtracted by actual. So

262 - 255 = 7

The residual is of 7 mg.