Exploring the Area of a Circle

What is the relationship between the circumference and diameter of a circle?

• Circumference is half the diameter.

• Circumference is pi times the diameter.

• Circumference is the square of the diameter.

• Circumference is twice the diameter.

How can you calculate the circumference if only the radius is given?

• Multiply the radius by pi.

• Divide the radius by pi.

• Multiply the radius by two and then by pi.

• Multiply the radius by two and then multiply by pi.

What method is used to estimate the area of a circle using grid paper?

• Calculating the radius squared times pi.

• Measuring the diameter with a ruler.

• Counting the total squares inside the circle.

• Using a compass to draw precise circles.

What does the area formula for a circle involve?

• Pi times the diameter squared.

• Pi times the radius squared.

• Diameter divided by the radius.

• Radius times the diameter.

How do you calculate the area of a circle with a radius of 7 inches?

• 49 pi square inches.

• 28 pi square inches.

• 14 pi square inches.

• 7 pi square inches.

What is the area of a circle with a radius of 3/2 inches?

• 2.25 pi square inches.

• 6 pi square inches.

• 3 pi square inches.

• 9/4 pi square inches.

How do you handle the area calculation when given the diameter instead of the radius?

• Square the diameter and multiply by pi.

• Use the diameter directly in the formula.

• Divide the diameter by two to find the radius first.

• Multiply the diameter by pi directly.

What is the correct area calculation for a circle with a diameter of 8 cm?

• 16 pi square centimeters.

• 32 pi square centimeters.

• 64 pi square centimeters.

• 4 pi square centimeters.

In a scaled drawing, if a circle's radius is 6 cm on paper and each 2 cm represents 5 feet, what is the real radius?

• 12 feet.

• 20 feet.

• 18 feet.

• 15 feet.

What is the area of a circle with a radius of five-sixteenths of an inch?

• 0.3 square inches.

• 0.5 square inches.

• 0.1 square inch.

• 1 square inch.