Why was the Area upset with the Perimeter?
Because the area thought the perimeter always went around the problem.
Perimeter is the total distance taken up around the outside of a shape.
Can you think of examples of where perimeter may be used?
A good example is if you are fencing a field, or building a wall around something. You will need to know the perimeter.
To find the perimeter
Just add up the lengths of each shape.
When you have a missing length such as in this example, break it down as shown above.
Perimeter = 10 + 2 + 6 + 6 + 4 + 8 = 36 cm.
Calculate the missing length. If the slant height isn't given you have to assume the slant height is 4 cm.
Perimeter = 4 + 10 + 10 = 24 cm
The missing side length is 11 cm and the length of the semi circle can be calculated by finding the circumference and dividing by 2.
Circumference = π x diameter
The missing length of the rectangle is 11 cm.
The circumference of the circle is π x 12 = 37.70 cm
12 + 11 + 11 + 37.70 cm = 71.70 cm
Lets get around these problems.