Name ______________________________
Circle Swirl
Partner and Independent Practice
Find the approximate area of each circle. Remember to write the formula on
the first line, substitute the value for r on the second line, and write the
approximate answer on the last line.
1.
2.
3.
r = 12 cm
A=
A=
A=
A=
A=
A=
A≈
A≈
A≈
A ≈ _______ cm2
A ≈_______ in.2
A ≈ ________ in.2
Choose the best answer for each question after showing your work.
4. The diameter of the circle that a shot-putter stands in is 7 ft. What is the approximate area of the
circle?
A.
49 π ft2
B.
12.25 π ft2
C.
196 π ft2
D.
7 π ft2
5. A cylindrical barrel has a diameter of 19.875 inches. Which of the following is the best estimate of the
circumference of the barrel in feet? (Hint: How many inches are in 1 foot?)
A.
10 ft
B.
2 ft
C.
5 ft
D.
1 ft
6. The diagram at right shows 2 circles with the same center at point F. Points E, F, and G are on line
segment DH. The diameter of the larger circle is 14 mm.
What is the radius of the smaller circle?
A.
mm
B.
7 mm
C.
11 mm
D.
8 mm
Property of Cy-Fair ISD Middle School Math Dept. (361)
Name ______________________________
Mixed Practice:
7. The rim of Mikayla’s cereal bowl has a circumference of 19 inches. Which of the following statements
is NOT true about Mikayla’s cereal bowl?
8.
9.
A.
The diameter of the cereal bowl is about 6 inches.
B.
The radius of the cereal bowl is about 12 inches.
C.
The radius of the cereal bowl is about 3 inches.
D.
The radius of the cereal bowl is half its diameter.
A circular railroad crossing sign has a diameter of 30 inches. Which measurement is closest to the
area of the sign in square inches?
A.
94.2 in.2
C.
706.5 in.2
B.
188.4 in.2
D.
286.6 in.2
A circular window has a diameter of 24 inches. Which of the following statements is
true about the circular window?
A.
The radius of the window is 48 inches.
B.
The radius of the window is 7.6 inches.
C.
The circumference of the window is about 75.4 inches.
D.
The circumference of the window is about 48 inches.
10. Josh is designing a dart board. The drawing of the board is shown below.
Which expression can be used to find the area of the larger circle in square inches?
6 in.
9 in.
A.
6(9)(3.14)
C.
(6  9)2  3.14
●
B.
(6  9)  3.14
D.
2
2
(9  3.14)  (6  3.14)
11. The figure shown here shows two circles. The smaller circle has a radius, BC, of 5 cm. Point E is
the center of the larger circle. What information is needed to find the length of segment BF?
A.
The circumference of the smaller circle.
B.
The diameter of the smaller circle.
C.
The length of segment CD.
D.
The length of segment DE.
Property of Cy-Fair ISD Middle School Math Dept. (361)