William’s car wheel has a diameter of 50 cm. What is the circumference of the wheel?
6. What is asked in the problem? 
A. The area of the wheel
B. the radius of the wheel
C. the diameter of the wheel
D. the circumference of the wheel
7. What is given? 
A. diameter of 50 cm
B. diameter of 60 cm
C. diameter of 70 cm
D. diameter of 80 cm
8. Which formula should be used? 
A. C = πd
B. C =2πd
C. C = 2πr
D. C = πr
9. Which is the correct number sentence?
A. C = 3.12 x 50cm
B. C = 3.13 x 50cm
C. C = 3.14 x 50cm
D. C = 3.15 x 50cm
10. What is the answer to the problem? 
A. The circumference of the wheel is 153 cm
B. The circumference of the wheel is 154 cm
C. The circumference of the wheel is 156 cm
D. The circumference of the wheel is 157 cm ​