Perimeter

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Perimeter

• A lesson in geometry for fifth or sixth grade
  students

This Power point was created by Sara Johnson
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Perimeter- the total distance or boundary around
a figure In order to stay in shape, Mike has
decided to walk around the outside of his yard.
His yard is a square with sides that are 112 feet
long. How far will he walk?
112 feet
Mikes yard
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Mike will walk around the outside of the yard, so
the distance he covers will be the same as the
perimeter of the yard.
112 feet
His yard is a square. You know that all the
sides of a square are the same length. Since one
side is 112 feet long, the other three sides are
the same.
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112 feet
If we were to walk around the yard with Mike,
wed also be walking the perimeter of it. If
we were to walk across side A we would walk
a distance of 112 feet. Walking along side B
would add another 112 feet to our distance (as
would walking sides C and D).
side A
side B
side D
112 feet
112 feet
side C
112 feet
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To find the distance we had walked (or the
perimeter of the yard), we would simply add
together the length of all the sides. side A
side B side C side D perimeter 112 feet112
feet112 feet112 feet448 feet So when Mike
walks around the outside of his yard he walks 448
feet. The perimeter of Mikes yard is 448 feet.
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To find the perimeter of a polygon, add the
measures of all the sides. Perimetersum of all
sides
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For other resources on perimeter and some
practice problems, visit Mrs. Glossers Math
Goodies website http//www.mathgoodies.com/lesson
s/vol1/perimeter.html
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10 cm
6 cm
8 cm
To find the perimeter of the above triangle, you
must add up the lengths of every side 6 cm 10
cm 8 cm 24 cm The perimeter of the triangle
is 24 cm.