Measuring Circles

A circle has radius 50 cm. Which of these is closest to its area?

• 157 cm²

• 314 cm²

• 7,854 cm²

• 15,708 cm²

Tags

CCSS.7.G.B.4

Does there appear to be a proportional relationship between the radius and circumference of a circle? Explain your reasoning.

• Yes, the points line up on a straight line that leads back to the origin.

• Yes, there is a Constant of Proportionality.

• No, the points line up on a straight line, but do not include the origin.

• No, there isn't a Constant of Proportionality.

Tags

CCSS.7.RP.A.2D

For each quantity, decide if circumference would be needed to calculate it.

• The distance around a circular track

• The total number of equally-sized tiles on a circular floor.

• The amount of oil it takes to cover the bottom of a frying pan.

• The distance your car will go with one turn of the wheels.

Find the area of the circle

• 56.52

• 254.34

• 1017.36

• 113.04

Tags

CCSS.7.G.B.4

What is the circumference?

• 36

• 18pi

• 108pi

• 36pi

Tags

CCSS.7.G.B.4

What is the diameter?

• 8

• 16

• 10

• 4

Tags

CCSS.7.G.B.4

What is the perimeter of the solid line around this figure, to the nearest WHOLE unit?

Tags

CCSS.3.MD.D.8

What is the area of this figure, to the nearest WHOLE square unit?

A groundskeeper needs grass seed to cover a circular field, 290 feet in diameter.

What is the area of the circular field to the nearest WHOLE square unit?

Tags

CCSS.7.G.B.4

A groundskeeper needs grass seed to cover a circular field, 290 feet in diameter.

A Store sells 50-pound bags of grass seed that covers about 20,000 square feet of field.

What is the least number of WHOLE bags the groundskeeper must buy to cover the circular field?

Tags

CCSS.HSG.C.B.5