Steve usually buys four books a month for the same price. Every August, his favorite bookstore holds a back-to-school sale and everything in the store is priced at 10 percent off. Steve takes advantage of the sale by buying six books in August. What happened to the amount of money that Steve spends on books in August, compared to other months?

The amount of money spent by Steve in August is 135% of the amount spent in other months

Step-by-step explanation:

Let the price of each book bought be x

Therefore amount spent on books by Steve in every other month = 4x

In August price of books is 0.9x and Steve bought 6 books.

Therefore amount spent by Steve in August = 5.4x

Therefore difference between amount spent by Steve in August & every other month = 5.4x - 4x = 1.4x

Therefore percentage increase of amount spent in August

(1.4x : 4x) * 100 = 35%