Question

1. a furious ap stats teacher wondered if playing music during an exam would increase scores. she had three classes of 30 students each. she decided to play music during the exam for one of the classes. the mosaic plot shows the results. a. what percent of the students who listened to music during the exam earned an a score on the exam? b. what percent of the students who didnt listen to music during the exam earned an a score on the exam? c. how much wider is the bar for “no music” than for “music”? explain why.

Explanation:

Step1: Identify relevant bars

Find the bars for 'Music' and 'No Music' in the mosaic - plot for grade A.

Step2: Measure bar - widths

Estimate the width of the bar for 'Music' and 'No Music' corresponding to grade A. Let's assume the width of the bar for 'Music' (grade A) is \(w_1\) and for 'No Music' (grade A) is \(w_2\).

Step3: Calculate the difference

To find how much wider one bar is than the other, we calculate \(|w_2 - w_1|\). From the plot, the width of the bar for 'No Music' (grade A) is approximately 40% and for 'Music' (grade A) is approximately 20%. So the difference is \(40 - 20=20\) percentage - points.

Answer:

The bar for 'No Music' is 20 percentage - points wider than the bar for 'Music' for students who earned an A score on the exam. This is because, from the relative - frequency mosaic plot, the proportion of students who didn't listen to music and got an A is around 40%, while the proportion of students who listened to music and got an A is around 20%.