To calculate the perimeter of the given figure, let's break down the shape based on the dimensions provided:

Description of the Shape

The figure is a stepped or "L"-shaped figure with various lengths marked. The sides are as follows:

1. The left vertical side is 40 mm.
2. The top horizontal side is 10 mm.
3. The next vertical side down from the top is 20 mm.
4. The horizontal side next to that is also 10 mm.
5. The final vertical drop to the bottom is 10 mm.
6. The bottom horizontal side is 35 mm.
7. The middle vertical drop is 10 mm.

Calculation of the Perimeter

To calculate the perimeter, sum the lengths of all outer sides:

1. Left vertical side: $40 \text{ mm}$
2. Top horizontal side: $10 \text{ mm}$
3. Vertical side down: $20 \text{ mm}$
4. Horizontal side across: $10 \text{ mm}$
5. Vertical drop down: $10 \text{ mm}$
6. Bottom horizontal side: $35 \text{ mm}$
7. Middle vertical side: $10 \text{ mm}$

So, the perimeter $P$ is calculated as follows:

$P = 40 + 10 + 20 + 10 + 10 + 35 + 10 = 135 \text{ mm}$

Final Answer

The perimeter of the figure is 135 mm.

Would you like further details or have any questions?

Here are some related questions:

1. How would the perimeter change if one of the side lengths increased?
2. Can the perimeter be calculated differently if the figure were rotated?
3. How would the perimeter change if the shape were scaled up by a factor of 2?
4. What would happen to the perimeter if the horizontal or vertical sides were reduced by half?
5. How does the perimeter of this L-shape compare to a rectangle with the same area?

Tip: To confirm the perimeter, it's helpful to mark each side you've accounted for on the diagram as you calculate the total.