Question

Please help!: Mrs. Carter baked a cake that was in the shape of a rectangular prism. The cake was 24 inches long, 15 inches wide and 3 inches high. She spread frosting on all four sides and the top. How many square inches of frosting did she use?

Answer 1

rectangle base: 24 x 15 = 360

triangle: 15 x 3 x 1/2= 45 x 1/2 = 22.5 x 4 (each side) 90 inches

total: 360 + 90 = 450 inches :)