Question

Assume you have noted the following prices for books and the number of pages that each book contains. book pages (x) price (y)

a 500 $6.90
b 700 7.40
c 750 9.10
d 590 6.40
e 560 7.40
f 650 7.10
g 475 5.10
a. Develop a least-squares estimated regression line.

Answer 1

To create a least-squares regression line, data is entered into a calculator or software to find the equation, which can then be used for predictions. Without the specific equation, one cannot predict costs for specific page numbers but can understand the concepts and typical procedures involved.

Step-by-step explanation:

The question is asking to develop a least-squares regression line based on the given data of book pages and prices. To create this line, one would typically input the given data points into a calculator or statistical software and use a regression function to find the equation of the line. Once the equation is obtained, in the form ŷ = a + bx, it is used to make predictions.

For a textbook with 400 pages, to predict the cost, we would substitute x = 400 into the regression equation. Similarly, to predict the cost for a textbook with 600 pages, x = 600 would be plugged into the equation. However, without the specific regression equation provided in the question, I cannot calculate these predictions.

The question also refers to calculating a correlation coefficient to assess the strength of the linear relationship between the number of pages and the price, and suggests a scenario where the correlation is not significant. A scatter plot is also a tool typically used to visually display the data and the least-squares regression line.