原帖由 kate;) 於 2006-12-5 07:36 PM 發表
i don't understand that the 3 questions ..
plz help me /3\


1. The diameter of a wheel is 0.5 m. How far does it travel in 10 revolutions? { Take π' = 3.14 }
10 x (0.5 π' ) = 15.6

2. A coin rolling along a straight line covers 110 cm in 14 revolutions. Find the diameter of the coin { Take π' = 22/7 }
where D be the diameter
110 = 14 x (22D/7)
D = 5/2

3. The difference between the radii of two circles is 3 cm. Find the difference in their circumferences. { Express your answer in terms of π }
2x 3 x π = 6π