Two trains starting at the same time from two stations 200 km apart and going in opposite directions cross each other at a distance of 110 km from one of the stations. What is the ratio of their speeds?  Choices
A) 21 : 9	B) 11 : 9	C) 71 : 9	D) 91 : 9	E) 21 : 2
Explanation:   In the same time, they cover 110 km and 90 km respectively.   {\color{11 : 9lue} \therefore } Ratio of their speeds = 110 : 90 = 11 : 9   Answer: 11 : 9
<result>B</result>
Two trains starting at the same time from two stations 200 km apart and going in opposite directions cross each other at a distance of 110 km from one of the stations. What is the ratio of their speeds?