The price of a used book in the bookstore after the percentage increase in its price is $7.50.
Percentage can be described as the fraction out of an amount that is usually expressed as a number out of hundred. Percentages are represented with this sign - %.
Price = 1.50 x ( 1 + 4)
1.5 x 5 = $7.50
To learn more about percentages, please check: https://brainly.com/question/25764815