6th Grade Math Textbook, Progress

Use the Fractional Value for 


You can use the fraction 
^272 
as an approximate

value for to find the circumference of a circle.

C 2 r

11

C

^21 

^272 

^72 
ft

11

C
22 ft

Use
3 to estimate the circumference. Then use 3.14 for


to find the circumference of each circle.

2 m 4 ft 10 yd 8.5 in.

3 ft^12

13. The diameter of Earth measures 14. A wheel has a diameter of 72 cm.
    about 13 000 km. What is its How far will a point on the wheel
    approximate circumference? travel in 3 complete turns?

Find the circumference. Use 


2

7

(^2)

for
.

5. d7 ft 6. r14 cm 7.d21 in. 8. d35 mm


6. d 1
   
   3
   4
   ft 10. d^1
   

2

5 
yd 11.r

1

2 
yd 12. r^2 

1

4 
ft

3 
^12 
ft
^72 
ft

^272 

3.14

Find the perimeter of each complex figure.

14 ft

4 cm

10 cm

12 m

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