The length of the rectangle is 15 cm and its width is 3 times less than the length. What is the perimeter of the rectangle?

The first step is to find out how wide the rectangle is.

To do this, divide the length of the rectangle (15 cm) by 3 (since the width is 3 times less than the length of the rectangle):

1) 15: 3 = 5 (cm) – the width of the rectangle.

In the second step, you need to find what the perimeter of the rectangle is.

To do this, in the formula for the perimeter of the rectangle (P = 2 (a + b)), we substitute the values, where a is the length, b is the width:

2) 2 * (15 + 5) = 40 (cm) – the perimeter of the rectangle.

1 m = 100 cm;

40 cm = 0.4 m.

Answer: 0.4 m.