Question

As the number of pages in a photo book increases, the prices of the book also increases. There is an additional shipping charge a 15%. The price of a book can be modeled by the equation below, where P= the price of the book, 20 is the printing charge, 0.5 is the charge per page, and x= the number of pages:
P=(20+0.5x) + 0.15(20+0.5x)
Jennifer wants to purchase a book but only has $62.10 to spend. What is the maximum number of pages she can have in her book

Answer 1

equate P as 62.10 since we are looking for the MAX value for x (then a legitimate one if necessary)

(20 + 0.5x) + (3 + 0.075x) = 62.1
= 0.575x + 23 = 62.1
x = (62.1-23)/0.575
x = 680