LESSON: Circumference of Circles

Objectives/Vocab

Objectives

  • Identify ratio of circumference to diameter as pi.
  • Find the circumference of circles given diameter or radius.
  • Find diameter or radius of circles given circumference.
  • Solve real world problems involving circumference of circles.

Vocabulary

Circumference
the measure of the distance around the outside edge of a circle.
Diameter
the measure of the distance across the center of a circle.
Radius
the measure of the distance half-way across the circle. It is the measure from the center to the outer edge. The radius is also half the length of the diameter.
Pi
the ratio of the diameter to the circumference, 3.14
Archimedes
a Greek mathematician and philosopher who identified 3.14 as pi.