Question

Whats the answer for this?

Answer 1

20 sit-ups

Explanation:

A regression line is a straight line that represents the best approximation of the linear relationship between two variables in a set of data points.

The general equation of a regression line is:

`\large\boxed{y=ax+b}`

where:

• y is the dependent variable (the variable we want to predict or explain).
• x is the independent variable (the variable used to predict y).
• a is the y-intercept of the line, which represents the value of y when x is zero.
• b is the slope of the line, which represents the rate of change of y with respect to changes in x.

In this case:

• The dependent variable is the number of sit-ups a person can do.
• The independent variable is the hours of TV watched per day.

Substitute the values of a and b from the linear regression analysis into the regression line equation:

`y=-1.24x+31.072`

To predict the number of sit-ups that a person who watches 9 hours of TV can do, substitute x = 9 into the regression equation and solve for y:

`y=-1.24(9)+31.072`

`y=-11.16+31.072`

`y=19.912`

Therefore, a person who watches 9 hours of TV can do 20 sit-ups (rounded to the nearest whole sit-up).