8th Grade - Area, Perimeter and Circumference

9

Each wheel on the back of a wagon has a diameter of 20 cm. Each wheel on the front has a diameter of 18 cm. By the time the wagon travels 50 meters, how many more revolutions has the front wheel made than a rear wheel? (round to nearest whole number)

855

Emily needs to walk through a circular farm field that has a diameter of 1500 feet. Because she is worried about destroying her new boots, she is thinking about going around the field. How much further will Emily's walk be if she decides to walk around the field instead of through it?

300

The length of a rectangle is increased to 2 times its original size and its width is increased to 3 times its original size. If the area of the new rectangle is equal to 1800 square meters, what is the area of the original rectangle?

62.8

Find the circumference of a circle inscribed inside a square with an area of 400 sq meters.

840

If carpet cost $7.00 a square yard, what would it cost to carpet a room that is 10 yards wide by 12 yards long?

5

Mike has a dog that is tied up in the center of his lawn with a 20 ft chain. The dog has killed the grass everywhere it can reach, so Mike is buying grass seed to replant the grass. If each package of grass seed is enough for 300 square feet., how many bags of seed will Mike need to buy?

20

The length of a rectangle is four times its width. If the area is 100 sq meters, what is the length of the rectangle?

51.6

One leg of a right triangle is 18 cm and its area is 108 square cm. Find its perimeter.

40

What is the height of of an isosceles right triangle that has an area of 800 sq feet?