Question

An engineer designed a square-shaped door of side 7 m for a house that he’s building.


a. What is the perimeter of the door in cm units?
b. What is the area of wood required for the door?

• A. a. 280 cm; b. 49 cm${}^2$
• B. a. 280cm; b. 490 cm${}^2$
• C. a. 2000cm; b. 4900 cm${}^2$
• D. a. 2800 cm; b. 49 m${}^2$

Answer 1

The correct option is D a. 2800 cm; b. 49 m${}^2$

The door designed by the engineer is square in shape.

a. The side of the square-shaped door is given as 7 m, but we have to find its perimeter in cm units.
To convert m into cm, we know {1 m = 100 cm }
=> 7 m = 7 × 100 = 700 cm

Perimeter of square = 4 × side
=> 4 × 700 = 2800 cm
Hence, the perimeter of the door = 2800 cm



b. To find the area of the door, we can find the area of the square Area = $sid{e}^2\Rightarrow 7\times 7=49m^2$