Leah is buying curtains for her bedroom window. she wants the certains to hang from the top of the window to the floor. the window is 4 feet high. the bottom of the window is 21/2 feet above the floor. how many inches long should leahs certains be?

Because the window is 4 feet and you need it to cover the window and the floor, you could start with the window. 4 feet at 12 inches per foot is 48 inches already. Then you would add the distance between the window and the floor, 21/2 feet is 10.5 feet. 10.5 * 12 inches is 126 inches. 126+48=174. You need 174 inches. See my pic

That they are numbers and related to each other.