Area of Circles and Rings

The video tutorial explains how to find the area of a red ring by calculating the areas of two circles and subtracting the smaller circle's area from the larger circle's area. The tutorial uses a step-by-step approach, starting with the introduction of the problem, followed by a strategy overview, detailed calculations using given radii, and concluding with the final calculation and approximation of the area. The use of 3.14 for pi and rounding to the nearest tenth is emphasized throughout the process.

What is the formula for the area of a circle?

• Area = Pi * r^2

• Area = 2 * Pi * r

• Area = 2 * Pi * r^2

• Area = Pi * d

Tags

CCSS.7.G.B.4

What is the general strategy to find the area of the red ring?

• Add the areas of the large and small circles

• Subtract the area of the small circle from the large circle

• Multiply the areas of the large and small circles

• Divide the area of the large circle by the small circle

Tags

CCSS.7.G.B.4

What is the radius of the large circle in the problem?

• 12 units

• 9 units

• 10 units

• 11 units

Tags

CCSS.HSG.GMD.A.1

What approximate value of Pi is used in the calculations?

• 3.20

• 3.14

• 3.00

• 3.50

Tags

CCSS.7.G.B.4

How is the area of the large circle calculated?

• Pi * 11

• Pi * 9

• Pi * 11^2

• Pi * 9^2

Tags

CCSS.7.G.B.4

What is the area of the small circle using the approximate value of Pi?

• 35.00 square units

• 30.00 square units

• 28.26 square units

• 24.34 square units

Tags

CCSS.7.G.B.4

What is the area of the large circle using the approximate value of Pi?

• 350.00 square units

• 400.00 square units

• 300.00 square units

• 379.94 square units

What is the final step in finding the area of the red ring?

• Divide the area of the large circle by the small circle

• Multiply the areas of both circles

• Subtract the area of the small circle from the large circle

• Add the areas of both circles

Tags

CCSS.5.NBT.B.7

To what decimal place is the final answer rounded?

• Hundredths

• Tenths

• Thousandths

• Whole number

Tags

CCSS.7.G.B.4

What is the approximate area of the red ring?

• 130.00 square units

• 125.64 square units

• 110.00 square units

• 100.00 square units

Tags

CCSS.7.G.B.4