Calculating Areas of Circles

This video tutorial explains how to calculate the area of partial circles, including quarter, three-quarter, and semi-circles. The process involves first calculating the area of the entire circle using the formula (radius squared times pi) and then adjusting for the partial section by multiplying by the fraction of the circle represented. Examples are provided for each type of partial circle, demonstrating the step-by-step calculation process.

What is the main focus of this video tutorial?

• Calculating the area of partial circles

• Calculating the circumference of full circles

• Understanding circle theorems

• Finding the diameter of circles

What is the formula for the area of a full circle?

• Radius squared times pi

• Radius times diameter times pi

• Diameter squared times pi

• 2 times radius times pi

In the first example, what is the radius of the partial circle?

• 2

• 3

• 5

• 4

How do you calculate the area of a quarter circle?

• Multiply the area of the full circle by 1/2

• Multiply the area of the full circle by 2

• Multiply the area of the full circle by 1/4

• Multiply the area of the full circle by 3/4

What is the area of the quarter circle in the first example?

• 4 pi

• 3 pi

• pi

• 2 pi

What is the first step in calculating the area of a partial circle?

• Measure the arc length

• Find the circumference of the circle

• Determine the diameter of the circle

• Calculate the area of the full circle

What is the area of a full circle with a radius of 2?

• 8 pi

• 6 pi

• 4 pi

• 2 pi

In the second example, what fraction of the circle is missing?

• 1/5

• 1/3

• 1/4

• 1/2

What is the radius of the circle in the second example?

• 3

• 5

• 4

• 6

How do you calculate the area of a three-quarters circle?

• Multiply the area of the full circle by 2

• Multiply the area of the full circle by 1/4

• Multiply the area of the full circle by 3/4

• Multiply the area of the full circle by 1/2