Arithmetic - Miscellaneous - Perimeter of Rectangles
Perimeter is the distance around a shape. Consider this rectangle:
This rectangle has a height of 13 units and a width of 14 units. Since there
are four sides to a rectangle you have to add the length of each side to
obtain the perimeter.
PERIMETER = 13 + 13 + 14 + 14 = 54 units
Remember units can be inches, feet, yards, meters, or any
other unit of length. We use the term units when the actual unit is left
unspecified.
Here's another rectangle for you to take a look at.
As you can see it has a height of 5 units and a length of 24 units. To
find the total distance around this object you simply add up the length of
each side.
PERIMETER = 5 + 5 + 24 + 24 = 58 units
Alternatively you could use multiplication as a slight short cut:
PERIMETER = 5 x 2 + 24 x 2 = 58 units
OR
PERIMETER = (5 + 24) x 2 = 58 units
If you happen to get a square then finding the perimeter is even easier:
Since all four sides are equal you can just multiply:
Of course you could find perimeters for pentagons, octagons, or any other
shape. In any case you just add up the length of all the sides and you have
the perimeter of the object.
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