Rob Schupbach Problem #3CRIN E07: Elementary Math Curriculum and InstructionDr. Margie Mason/Ms. Rachael CoferSeptember 23, 2011Topic: Measurement: Perimeter and Area—Grade 5 (SOL 5.8 a, b)Expected Heuristics: Use a picture; Use logical reasoning; Use equations andformulasMore for the FloorNika is selecting floor tiles for her room in her familys new house. No tiles will beput down in the closets. Each tile is 1 foot square and costs $0.60. All theintersecting sides of the tiles meet at right angles. How much will the tiles cost if there are no tiles left over?Answer: Cost: $105.60Complete Solutions: There are 176 ft². Since each tile is 1 ft², 176 tiles areneeded.Multiply: 176 x $0.60 = $105.60, the cost of the tiles.Here is another way to solve the problem. Find the total area of the room: 15 ft x 14 ft = 210 ft². Find the total area of the two closets: 6 ft x 3 ft = 18 ft², the area of one closet; 4 ft x 4 ft = 16 ft², the area of the other closet. The total for both closets is 18 ft² + 16 ft², or 34 ft². Subtract: 210 ft² − 34 ft² = 176 ft² of floor space, or 176 tiles needed. Multiply: 176 x $0.60 = $105.60, the cost of the tiles.
Rob Schupbach Problem #3CRIN E07: Elementary Math Curriculum and InstructionDr. Margie Mason/Ms. Rachael CoferSeptember 23, 2011Houghton Mifflin Math. (2011). Retrieved September 23, 2011, from http://www.eduplace.com/kids/mw/g_5.html