Circle Terms
The distance from the center of a circle to the outside, also half of the diameter
What is radius
A circle has a diameter or 6, what is the area of the circle? Round to the nearest tenth if needed.
28.26 rounds to 28.3
Find the surface area of a tablecloth that is 9 feet wide by 16 feet long.
144 square feet
Explain how you can find diameter given the radius
Double it (multiply it by 2)
What is the line that goes through a circle, and through the mid point
Diameter
What is the circumference of a circle with a radius of 8 inches?
50.24 inches
What is the surface area of a cylinder that has a diameter of 4.6 and a height of 2.5? (Do not round during any of the stages)
Area of top and bottom circle = 16.6106 x 2 = 33.2212
C = 14.444
Area of "label" = 14.444 x 2.5 = 36.11
Total SA = 33.2212 + 36.11 = 69.3312
How many degrees are in a circle?
360
Describe circumference
The distance around a circle
What is the area of a circle with a diameter of 9? Round to the nearest tenth if needed.
63.6 units squared
What is the area of only the label of a soup can that has a radius of 4, and a height of five?
c = 8 x 3.14 = 25.12
Area of label = 5 x 25.12 = 125.6
The distance around a circle, ...the perimeter of a circle..
Describe area (of a circle)
What is the circumference of a circle with a diameter of 27 cm?
84.78 cm
Mrs. Streich is wrapping a gift and wants to make sure she has enough wrapping paper. The box is 16 inches long, 9 inches wide, and 5 inches height. How much paper does she need?
288 +160 +90 = 538 square inches of paper
What is the difference between area and surface area?
Area is for 2 dimensional figures, like a square or a circle. Surface area is the area of all the faces of a 3 dimensional object, like a box (rectangular prism) or a cylinder.
What is the ratio of diameter to circumference more commonly know as?
Pi
The radius of a circle is 4meters, find both the area and circumference
25.12 meters = circumference
50.24 meters squared = area
What is the volume of a cylinder with a radius of 20 inches and a height of 45 inches?
56,520 cubic inches
If a pie graph shows that 42% of students' favorite class is social studies, what would the central angle be?
Set up a proportion: 42/100 = x/360
151.2 degrees