Question

khalils math teacher plots student grades on their weekly quizzes against the number of hours they say they study on the pair of coordinate axes and then draws the line of best fit. calculate the residual for the data point that corresponds to 3 hours of study and a score of 83.9 points.

Explanation:

Step1: Recall the formula for residual

Residual = Observed value - Predicted value.

Step2: Identify the observed and predicted values

The observed value (quiz score) is \( y_{observed}=83.9\).
From the line of best - fit, when \(x = 3\) (hours of study), the predicted value \(y_{predicted}=80\).

Step3: Calculate the residual

Residual \(=y_{observed}-y_{predicted}\)
Residual \(=83.9 - 80\)

Answer:

\(3.9\)