Chapter 4.3, Problem 98E

(a)

To determine

To explain how the graph illustrates the concept of sampling variability.

Explanation of Solution

Sampling variability is how much an estimate varies between samples i.e. how much the estimate varies from the true result. By looking at the graph above we can say that the graph is approximately symmetrically skewed as both the left and right side of the graph looks the same. From this we can say that the mean of the data is approximately in the middle of the graph. And we know that the true population has the graph skewed symmetrically only and thus the mean is in the middle of it. Thus, the graph illustrate the concept of sampling variability as we can compare the graph with the true population by the position of the mean.

(b)

To determine

To explain is there convincing evidence that fewer than $43\%$ of people born since $1993$ were born on Friday, Saturday or Sunday.

Answer to Problem 98E

Yes.

Explanation of Solution

Yes, there is convincing evidence that fewer than $43\%$ of people born since $1993$ were born on Friday, Saturday or Sundaybecause the graph is approximately symmetrically skewed as both the left and right side of the graph looks the same. From this we can say that the mean of the data is approximately in the middle of the graph which is nearly close to the true population. Thus, we can say that fewer than $43\%$ of people born since $1993$ were born on Friday, Saturday or Sunday.