Area
Circumference
Area or Circumference
Miscellaneous
100
* A circle has a radius of 40 in. Which of these is closest to the area?
a. 126 in^2
b. 251 in^2
c. 5,025 in^2
d. 10,048in^2
c. 5,025 in^2
100
* A circle has a radius of 40 in. Which of these is closest to the circumference?
a. 126 in
b. 251 in
c. 5,025 in
d. 10,048in
b. 251 in
100
* For each quantity, decide whether circumference or area would be needed to calculate it.
a. The distance your bike travels with 1 turn of the tires.
b. The amount of frosting someone can fit on a circular cookie.
a. circumference
b. area
100
* The following table and graph show the relationship between diameter and circumference of circles of different sizes. Is there a proportional relationship between the 2 quantities? Explain why or why not.
Yes because there is a linear pattern and the set of points lie on/near a line that goes through (0,0).
200
* A circle has a diameter of 30 cm. Which of these is closest to the area?
a. 1,413 cm^2
b. 706 cm^2
c. 188 cm^2
d. 94 cm^2
b. 706 cm^2
200
* A circle has a diameter of 30 cm. Which of these is closest to the circumference?
a. 1,413 cm
b. 706 cm
c. 188 cm
d. 94 cm
d. 94 cm
200
* For each quantity, decide whether circumference or area would be needed to calculate it.
a. The total soil it would take to fill a layer of a circular flower bed.
b. The distance someone walks around a circular walking path.
a. area
b. circumference
200
Find the distance travelled by the tip of the second hand of a clock in 15 minutes if the hand is 6 cm long.
565.2 cm
300
If the area of a circle is 225pi in^2, what is the length of the radius?
15in
300
If the circumference of a circle is 34pi in, what is the length of the radius?
17 in
300
* What is the perimeter of this figure, to the nearest unit?
41 inches (in terms of pi: 16 + 8pi inches)
300
Arthur ran around a circular field 3 times. If he ran a total distance of 750 m, what is the diameter and radius of the field?
d = 79.6m, r = 39.8m
400
* The shape is composed of three squares and two semicircles. The squares have a side length of 5. Find the area and leave it in terms of pi.
75 + 25pi units^2 OR
25 + 25 + 25 + 25pi units^2
400
* The shape is composed of three squares and two semicircles. The squares have a side length of 5. Find the perimeter and leave it in terms of pi.
20 + 10pi units OR
10 + 10 + 5pi + 5pi units
400
* What is the area of this figure, to the nearest unit?
114 inches^2 (in terms of pi: 64 + 16pi inches^2)
400
* A groundskeeper needs grass seed to cover a circular field, 120 yards in diameter.
A store sells 40-pound bags of grass seed. One pound of grass seed covers about 200 square yards of field.
What is the smallest number of bags the groundskeeper must buy to cover the circular field?
56.52lbs rounded up: 57 lbs
1bag=40lbs, 2bags=80lbs. They need to buy 2 bags to cover the grass.