ANSWERS
CIRCLES - CIRCUMFERENCE
Words you should know.
THE CIRCUMFERENCE OF A CIRCLE IS THE DISTANCE AROUND IT.
IT'S THE SAME AS THE PERIMETER BUT FOR CIRCLES.
THE DIAMETER OF A CIRCLE IS A LINE SEGMENT THAT CONNECTS TWO POINTS ON THE
CIRCLE AND PASSES THROUGH THE CENTER. IT'S THE DISTANCE ACROSS THE MIDDLE.
THE RADIUS IS HALF OF THE DIAMETER. 2 x R = D OR 2r = d.
π , CALLED PI , IS THE ANSWER YOU ALWAYS GET WHEN YOU
Circumference
Diameter =
MEASURE THE CIRCUMFERENCE OF ANY CIRCLE AND DIVIDE IT
BY THE DIAMETER OF THE SAME CIRCLE. YOU CAN APPROXIMATE
π TO 3.14.
Now your turn. Complete each equation by filling in the empty space.
1.
Circumference =
2.
Diameter =
3.
Circumference =
Diameter
x
Circumference
Radius
2 x
x
Find the missing Circumference, Diameter, or Radius for each circle.
APPROXIMATE π TO 3.14.
Circumference = 1.57 miles
Diameter = 7.5 mm
4.
23.55mm
Circumference = 23.55
6.
miles
Diameter = 0.5 0.5
144.44 m
Circumference = 144.44
C = 62.8 cm
7.
Radius =
8.
10 cm
10
MATHCRUSH.COM
Radius = 23 meters
5.
r = 52 miles
326.56 miles
Circumference = 326.56
9.
d = 83 in
260.62 in
Circumference = 260.62
LEVEL 2