Question

A scale drawing of a square has a side length of 6 millimeters. The drawing has a scale of 1 mm : 7 km. Find the actual perimeter and area of the square.

Answer 1

The real perimeter is:

`P= 24 mm *(7 km)/(1mm)= 168 km`

And the area would be:

`P = 36mm^2 *((7km)^2)/((1mm)^2) = 1764 km^2`

Explanation:

For this case we know one side of a square given 6mm.

We can begin calculating the perimeter for the scale figure with this formula:

`P = 4x = 4*6 mm =24 mm`

The area for this case is given by:

`A = x^2 = 6mm^2 = 36 mm^2`

And we know that the drawing has a scale of 1 mm : 7 km and if we convert the perimeter to km we got:

`P= 24 mm *(7 km)/(1mm)= 168 km`

And the area would be:

`P = 36mm^2 *((7km)^2)/((1mm)^2) = 1764 km^2`