Answer:
21. D = 5.67(rounded to the hundredths)
R = 2.84(rounded to the hundredths)
22. D = 13.4
C = 42.08(rounded to the hundredths)
23. C = 33.28(rounded to the hundredths)
R = 5.3
24. D = 1
R = 1.57 or pi/2
Step-by-step explanation:
Formula: C/pi = D
D = 2r
pi = 3.14
21. D = 17.8/3.14 = 5.67(rounded to the hundredths)
R = 5.67/2 = 2.84(rounded to the hundredths)
22. D = 6.7*2 = 13.4
C = 13.4 * 3.14 = 42.08 (rounded to the hundredths)
23. C = 10.6 * 3.14 = 33.28(rounded to the hundredths)
R = 10.6/2 = 5.3
24. D = 3.14/3.14 = 1
R = 3.14/2 = 1.57 or pi/2