7th 8-6 Solve Problems Involving Area of Circles

A certain coin is a circle with diameter 18 mm. What is the exact area of either face of the​ coin?

• $18\pi$
  

• $81\pi$

• $9\pi$

• $324\pi$

The radius of a circular sign is 12 inches. Equal parts of the sign are painted red and yellow. How many square inches are painted each​ color? Use 3.14 for π.

•  $12\pi$ 
  

•  $72\pi$ 

•  $6\pi$ 

•  $144\pi$ 

A water sprinkler sends water out in a circular pattern. What area will be watered if the radius of the spray from the sprinkler is 18​ ft?

• 324

• 1017

• 254

• 113

How many times greater is the area of Circle 1 than the area of Circle 2​? 

• 9

• 3

• 13.5

• 12

The diameter of Circle J is 18 cm. The diameter of Circle K is 31 cm. Which circle has the greater area and by how​ much?

• The area of Circle K is about 2000 cm2 greater than the area of Circle J.

• The area of Circle K is about 500 cm2 greater than the area of Circle J.

• The area of Circle J is about 2000 cm2 greater than the area of Circle K.

• The area of Circle J is about 500 cm2 greater than the area of Circle K.

You just finished planting​ avocados, carrots,​ radishes, tomatoes, and spinach in her new garden. The garden is a circle whose diameter is 50 yards. If you planted equal regions of each​ vegetable, what is the area of your garden has carrots​?

•  $2500\pi$ 
  

•  $500\pi$ 

•  $625\pi$ 

•  $125\pi$ 

The circumference of a circular patio is 53.38 feet. What is the area of the​ patio? Use 3.14 for an approximation for π.

• 17

• 8.5

• 72.25

• 226.9

The area of a circular window is 113.04 square inches. What is the diameter of the​ window? Use 3.14 for π.

• 12

• 72

• 6

• 226

The area of a circular window is 113.04 square inches. What is the circumfrence of the​ window? Use 3.14 for π.

• 37.7

• 72.1

• 18.9

• 226.5

The figure is made by attaching semicircles to each side of an​ 11-ft-by-11-ft square. Find the area enclosed by the figure.

• 155.54

• 215.99

• 121

• 94.99