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Course: Praxis Core Math > Unit 1
Lesson 5: Geometry- Properties of shapes | Lesson
- Properties of shapes | Worked example
- Angles | Lesson
- Angles | Worked example
- Congruence and similarity | Lesson
- Congruence and similarity | Worked example
- Circles | Lesson
- Circles | Worked example
- Perimeter, area, and volume | Lesson
- Perimeter, area, and volume | Worked example
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Perimeter, area, and volume | Lesson
What are perimeter, area, and volume?
The perimeter, , of a polygon is the total length around the polygon's edges. When we add up all the side lengths of a polygon, we get its perimeter. For the figure below, the perimeter is:
The area, , of a polygon is the amount of flat space inside the polygon's edges. Area is measured in square units such as square miles. Different polygons have their own area formulas.
The volume, , of an object is the amount of space that object occupies. Volume is measured in cubic units such as cubic centimeters.
What skills are tested?
- Calculating the perimeter of a polygon
- Calculating a side length given the perimeter
- Calculating the area of a polygon
- Calculating a length given the area
- Calculating the volume of an object
- Calculating a length given the volume
Which perimeter formulas are on the test?
For a , each side has the same length, . The formula is:
For a , two sides have length , and two sides have width . The formula is:
With each formula, we can also calculate the side lengths when is given. To do so, we:
- Write down the appropriate equation.
- Plug in known values.
- Solve for
, , or .
Which area formulas are on the test?
For a , each side has the same length, . The formula is:
For a , two sides have length , and two sides have width . The formula is:
For a , we're concerned with the base and the height . The formula is:
For a with base and the height , the formula is:
With each formula, we can also calculate one of the linear dimensions when is given. To do so, we:
- Write down the appropriate equation.
- Plug in known values.
- Solve for the linear dimension.
Which volume formulas are on the test?
For a with length , width , and height , the formula is:
We can also calculate one of the linear dimensions when is given. To do so, we:
- Write down the volume equation.
- Plug in known values.
- Solve for
, , or .
Your turn!
Things to remember
Shape | Perimeter ( |
---|---|
Shape | Area ( |
---|---|
Shape | Volume ( |
---|---|
Want to join the conversation?
- can volume, area, and permeter have a formula together.(4 votes)
- That was really ok and hard did not learn fraction perimeter volume and area!(3 votes)
- What the heck is this from ohio?(2 votes)
- How do you solve for the volume of a cylinder(1 vote)
- Find the area of its circular base, then multiply by the height.(2 votes)
- Do we need to memorize all area and Volume formulas or do we get a chart in the test?(1 vote)
- You will not be provided formula charts for this test. You will have to memorize and and apply these concepts without help.(1 vote)