Finding Areas of Semi-Circles and Quarter-Circles

This video tutorial explains how to calculate the area of semi-circles and quarter circles. It begins with a review of the area formula for a full circle, pi r squared, and then demonstrates how to adjust this formula for semi-circles and quarter circles by dividing by two and four, respectively. The tutorial includes several examples with different radii and diameters, showing both numerical calculations and expressions in terms of Pi. Each example is broken down step-by-step to ensure understanding.

What is the formula to calculate the area of a circle?

• Area = 2 * Pi * diameter

• Area = Pi * diameter

• Area = Pi * radius squared

• Area = 2 * Pi * radius

Tags

CCSS.7.G.B.4

If the radius of a circle is doubled, how does the area change?

• It quadruples

• It doubles

• It remains the same

• It halves

Tags

CCSS.7.G.B.4

How do you calculate the area of a semicircle with a radius of 7 meters?

• Pi * 7 * 7 / 2

• 2 * Pi * 7

• Pi * 7 * 7

• Pi * 14 * 14 / 2

Tags

CCSS.7.G.B.4

What is the area of a quarter circle with a radius of 8 centimeters?

• 200.96 cm squared

• 25.12 cm squared

• 100.48 cm squared

• 50.24 cm squared

Tags

CCSS.7.G.B.4

If a semicircle has a diameter of 12 meters, what is its radius?

• 3 meters

• 24 meters

• 12 meters

• 6 meters

Tags

CCSS.7.G.B.4

Calculate the area of a quarter circle when the radius is 5 centimeters.

• 9.8125 cm squared

• 78.5 cm squared

• 39.25 cm squared

• 19.625 cm squared

Tags

CCSS.7.G.B.4

What is the area of a quarter circle with a radius of 13 inches?

• 132.665 inches squared

• 265.33 inches squared

• 66.3325 inches squared

• 530.66 inches squared

Tags

CCSS.7.G.B.4

How do you find the area of a semicircle with a diameter of 2 meters?

• 1.57 meters squared

• 3.14 meters squared

• 6.28 meters squared

• 0.785 meters squared

Tags

CCSS.7.G.B.4

Express the area of a semicircle with a diameter of 18 feet in terms of Pi.

• 162 Pi feet squared

• 40.5 Pi feet squared

• 81 Pi feet squared

• 20.25 Pi feet squared

Tags

CCSS.7.G.B.4

What is the area of a quarter circle in terms of Pi if the radius is 14 millimeters?

• 24.5 Pi mm squared

• 49 Pi mm squared

• 98 Pi mm squared

• 196 Pi mm squared

Tags

CCSS.7.G.B.4