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Author: Simone Grey
  • Develop techniques for estimating the area of circles.
  • Develop strategies for comparing and organizing data.
  • Use ideas about area and perimeter to solve practical problems.
  • Continue to develop a conceptual understanding of area and perimeter.

In this tutorial, you will review and learn important basic concepts to find the area and perimeter of circles.


Wednesday, March 13, 2013: The questions for tonight's homework assignments can be found at .

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Circles: Circumference, Diameter & Radius (Part 1)

NOTICE: If you were having trouble viewing the video before it has been fixed. Sorry. =)

In this tutorial, you will learn about the important basic concepts needed to find the circumference and area of circles. Please be sure to have your notebook with you as you are watching it. Write down anything that YOU feel is important and will help you remember the key facts! You are encouraged to watch the tutorial, take a break, then watch it again. Just in case you missed something. =)

Don't forget to complete the questions afterwards.

Circles: Circumference, Diameter & Radius (Part 2)

In this tutorial, you will continue working on sample problems as discuss in the first tutorials.

Don't forget to complete the questions afterwards.

Circumference, Diameter & Radius

Review slides for practice problems and notes.

Radius - Diameter - Circumference

It would be a good idea to copy this into your notebook.

Where does TT (pi) come from?

For those of you who may be wondering where TT (pi) comes from, here is a cool video that shows you. It's simply the number you get when you divide the circumference by the diameter. As TT (pi) is an irrational number (it never ends), it's easier to simply write it as a symbol, rather than attempt to write out 3.14159265358979323846264338327950288419716939937510582097494459230781
04287554687311595628638823537875937519577818577805321712268066130019 27876611195909216420198968792314560827586240560078346756......

Imagine having to write that every time you needed to do a math problem.

Circle Music Video

From Fantastikos Mathematikos DVD and CD: 15 math topics set to original music and animation by Peter Weatherall.

Worksheet: Circumference of a Circle

Directions: Find the circumference of each circle. Use 3.14 for pi.


Worksheet: Radius & Diameter

Directions: Find the radius and diameter of each circle.


Worksheet: Circles

Directions: Write the names of each circle, radius and diameter.


Homework Questions: Wednesday, March 13