Mara wants to use tiles to cover the bottom of a rectangular box that measures 24 inches long by 2 inches wide. She has 20 small
square tiles with side lengths of 1 inch and 10 large square tiles with side lengths of 2 inches. If Mara uses all the small tiles first, how many large tiles will she need to use?
7. Because the 20 square tiles only fill in 20 square inches of the box. 7*4, 4 equaling the area of the big tiles, would equal 28 and 28+20=48. hope this helps.