Circumference and area of circle calculations are not very difficult IF your child is comfortable with the required knowledge of Pi.
In this section I am making the assumption that this is the case. If your child is not very comfortable with Pi, please take a few moments to
read our section covering this topic, which deals with what Pi is, how to calculate it's value and a lovely project for your student to do.
This section is STEP 3: of our circle geometry area.
Step 1: Know the circles construction
First a very quick recap of what the Circumference and Area of the circle are:
Area Is ALL the space inside the outer line of the circle. It is measured in SQUARE UNITS.
Circumference - Is the outline of the circle. It is measured in UNITS as it is a length. The circumference of a circle is the same as the perimeter of other shapes.
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What this equation tells us that we must first, square the value of the radius; then multiply this result by Pi, and the result in Square Units is the area of the circle. Don't get caught out if you are given the value of the Diameter. If this is the case, you will have to half this first, to calculate the length of the radius. |
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This equation tells us that we must multiply the Diameter of the circle by Pi to calculate the value of the perimeter/Circumference of the the circle. Don't get caught out if you are given the value of the Radius. If this is the case, you will have to multiply it by two first, to calculate the length of the diameter. |
I am sure you will find all the information and worksheets you need here, however if there is anything you cannot find please don't hesitate to contact me or simply visit the MathMomentumCommunity and join the conversation!
I love to hear from my readers, and with a little feedback and a few suggestions I can make this a great resource for parents, teachers and tutors alike.
Be sure to explore everything on this site starting at the home page.
Circumference and Area of Circle Calculations to our Circle Geometry Section or Explore all the other Geometric shapes areas of this site.