The Room Redesign

Pre-Algebra · Axiom Academy

Redesign a bedroom on a fixed budget: find each surface's area, multiply by its price, add up the cost, and check it against what you can spend. 1. The Floor Is Just Length × Width Before pricing anything, you need to know how much surface you're covering. The floor is a rectangle, so its area is simply the length times the width. Watch the room tile over with 1-foot squares — count the rows of squares and you've counted the area. 2. Walls, Then Turn Area Into Paint Cost The four walls are rectangles too, each as tall as the 8 ft ceiling. The two long walls are 15 ft wide and the two short walls are 12 ft wide. Watch all four fold flat and fill in to give the total wall area — then that area gets converted into gallons and dollars. Each is , so both together are . One gallon covers , and you can only buy whole gallons. Paint costs 25 a gallon. Cost = gallons × price. 3. Carpet Cost, and Adding It Up Carpet is priced by the square foot, so its cost is a straight multiplication: price per square foot times the floor area from Step 1. Watch the cost bar climb as the carpet fills the 180 ft² floor — then the paint cost stacks on top to give the running total. You've spent 885 on paint and carpet, and the budget is 1,500 . The question "how much is left for furniture?" is an inequality . Watch the cost bar rise toward the budget line — the gap that's left is your spending room. Spend up to 615 on furniture and decorations and the total stays at or under 1,500 .

This is the written version of the interactive lesson above. See the full Pre-Algebra course.