The two rectangles have the same area. The length is 320cm, width is 18dm.

The two rectangles have the same area. The length is 320cm, width is 18dm. What is the perimeter of the second rectangle if its width is 4 times less than the length of the first rectangle?

First, you need to convert the width of the first rectangle from decimeters to centimeters.

Since 1 dm – 10 cm, we get:

18 * 10 = 180 cm.

Find the area of the rectangles.

We multiply the length of the first rectangle by its width.

320 * 180 = 57600 cm2

Determine the width of the second rectangle.

To do this, divide the length of the first rectangle by the given difference, namely 4.

320/4 = 80 cm.

Find the length of the second rectangle.

We divide the area by the width.

57600/80 = 720 cm.

We define the perimeter.

2 * (720 + 80) = 2 * 800 = 1600 cm.

Answer: 1600 cm.