Area and Radius Calculations

Mrs. Groovy Groves guides students through Lesson 9, Unit 3, focusing on calculating areas of circles and comparing shaded regions in geometric figures. The lesson includes three activities: calculating the area of a field, comparing areas of shaded regions in different figures, and determining the area of a running track. The lesson emphasizes understanding geometric properties and applying formulas for area calculation.

What is the radius of a circle if the diameter is 800 meters?

• 800 meters

• 600 meters

• 400 meters

• 200 meters

How do you find the area of a shaded region in a square with a circle inside?

• Divide the area of the square by the area of the circle

• Multiply the area of the square by the area of the circle

• Subtract the area of the circle from the area of the square

• Add the area of the square and the circle

If a square has a side length of 12 units, what is the area of the square?

• 24 units

• 144 units

• 36 units

• 12 units

In figure B, if the diameter of each circle is 6, what is the radius?

• 3

• 4

• 1

• 2

How many circles are there in figure C if each has a radius of 2?

• 3

• 12

• 6

• 9

What is the approximate area of a circle with a radius of 1, using pi as 3.14?

• 3.14

• 6.28

• 9.42

• 12.56

How much larger is figure E compared to figure D?

• 0.23 units

• 0.53 units

• 0.33 units

• 0.43 units

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

• Length x Width

• Length + Width

• Length / Width

• Length - Width

If the diameter of a circle is 92.52, what is the radius?

• 23.13

• 36.26

• 46.26

• 56.26

What is the final calculated area of the running track?

• 3,186 meters squared

• 4,186 meters squared

• 6,186 meters squared

• 5,186 meters squared