A truck covers a distance of 200 metres in 1 minute whereas a bus covers a distance of 100kms in 50minutes. The ratio of their speeds is?
Choose the correct choice from the following answers:	A) 2 : 3	B) ratio 1 : 5	C) ratio 1 : 10	D) ratio 9 : 13	E) ratio 7 : 15

Rationale: "ratio of speeds = ( 200 / 60 ) 18 / 5 : 60 * 100 / 50 = 12 : 120 = 1 : 10 answer is c"
Answer: C