Use the information below to answer questions 13-14.
A shop keeper in the bookstore arranges the boxed sets of books as shown below. Each box contains 9 books.
How many books are there in all based on the passage above?
• Write an equation
• Solve using a letter to represent the unknown
Question 14
14.
Mrs. Colterman figures out how many books are in the arrangement. Her work is shown below. Explain Mrs. Colterman's strategy in words and numbers.
10 x 10 - 10 = 90
Question 15
15.
In the bookstore, Matt buys 3 boxes of pens. Each box contains 2 bundles of 10 gray pens. His friend buys 6 packs of pens. Each pack contains 10 black pens. Explain how the equation below shows how Mat and his friend buy the same number of pens.
3 x 2 x 10 = 6 x 10
Question 16
16.
Mrs. Fennessy and her friends notice a sale at the store. Compare the crossed out prices to the new sale prices. If all the sale prices are calculated in the same way, what would the sale price be on an item that originally cost $24? Use words and equations to explain how you know.