This Instructional Activity is a part of the Lesson 7, Unit 3, Grade 7. How did the change in the dimensions on the second problem change how you approached the problem? The widths of the posters are expressed in a different unit than the width of the room. This also makes the problem more difficult. Since this problem is more difficult than the first, what additional steps are required to solve the problem? The widths must be in the same units. Therefore, you must either convert feet to inches or convert inches to feet.