Geometry: Measurements

Problem : If a circle's radius is 4, what is its circumference?

Problem : If a circle's circumference is 24Π , what is its radius?

Problem : A 20 degree arc is what fraction of the circumference?

Problem : What is the length of the major arc pictured below? (C is the center of the circle)

Problem : A circle has a chord of length ten. What is the minimum circumference of the circle?