To solve this problem, let’s break down how to find the perimeter of the given shape.

The shape consists of:

1. A rectangular base with length 18 m and height 6 m.
2. Two semicircles on top, combined to form a full circle of diameter 6 m (equal to the width of the rectangle).

Steps to Find the Perimeter:

1. Perimeter of the Rectangle (excluding the top side):

   • The rectangle has two vertical sides of 6 m each and a bottom side of 18 m.
   • Total length of these three sides: $6 + 6 + 18 = 30$ m.

2. Circumference of the Full Circle on Top:

   • Since the diameter of the circle is 6 m, its radius $r$ is $\frac{6}{2} = 3$ m.
   • Using $\pi = \frac{22}{7}$, the circumference $C$ of the circle is: $C = 2 \pi r = 2 \times \frac{22}{7} \times 3 = \frac{132}{7} \approx 18.86 \text{ m}$

3. Total Perimeter:

   • Add the perimeter of the rectangle (30 m) and the circumference of the circle (18.86 m): $\text{Total Perimeter} = 30 + 18.86 = 48.86 \text{ m}$

Final Answer:

The perimeter of the figure is approximately 48.86 meters.

Would you like more details on any of the steps?

Here are five questions to deepen understanding:

1. How do you calculate the circumference of a circle if only the diameter is given?
2. Why is only half the circumference of a full circle used if it were a semicircle?
3. How does changing the value of $\pi$ affect the answer?
4. What would happen to the perimeter if the rectangle’s width was increased?
5. How can we apply similar steps to irregular shapes?

Tip: Always check if parts of a shape can form common shapes (like a full circle) to simplify perimeter or area calculations.