Find the surface area. Round to the nearest whole number.

Question

Answer 1

The total surface area is the sum of the areas of all six faces: 4 rectangles and 2 trapezoids. The area of each rectangle is its length times its width. For the rectangle on top, the area is 6 x 7 = 42 sq. yd. You can do the other 3 rectangles. The area of a trapezoid is (1/2) x (sum of the bases) x height. They give you the bases (7 yd and 3 yd) and the height (3.5 yd), so use the formula to compute the area of each trapezoid.

Again, the total surface area = sum of the areas of all six faces. Tell me what you get and I'll tell you if it's right.

Answer 2

Isbella,

There are 6 plane surfaces in this solid:

The bottom is a rectangle: (3 yd)•(6 yd) = 18 yd²

The top is a rectangle: (7 yd)•(6 yd) = 42 yd²

Each of the 2 angled ends is a rectangle: (4 yd)•(6 yd) = 24 yd²

Each of the remaining 2 faces is a trapezoid: [(3 yd + 7 yd)/2]•(3.5 yd) = 17.5 yd²

The total is (18 + 42 + 2•24 + 2•17.5)yd² = 143 yd²