Question

Two different sizes of square metal duct are joined by a piece that is a frustum of a pyramid. Find the lateral surface area, if the small end is square with one side of length 17 in. and the larger square end is of length 19 in. on one side with a slant height of 2 in.

Answer 1

288 in²

Explanation:

The formula used to solve this question is :

Lateral Surface Area = s( P1 + P2)

Where s = slant height = 2 inches

P1 and P2 = Perimeter of the bases

Perimeter of base 1 = 4 × length of the end of the small square

4 × 17 inches = 68 inches

Perimeter of base 2 = 4 × length of the end of the large square

4 × 19 inches = 76 inches

Lateral Surface Area = 2 × (68 + 76)

= 2 × 144

= 288 in²