A goods train leaves a station at a certain time and at a fixed speed. After ^hours, an express train leaves the same station and moves in the same direction at a uniform speed of 90 kmph. This train catches up the goods train in 4 hours. Find the speed of the goods train.
Choose the correct choice from the following answers:	A) 15 kmph	B) 36 kmph	C) 21 kmph	D) 17 kmph	E) 19 kmph
Let the speed of the goods train be x kmph.   Distance covered by goods train in 10 hours= Distance covered by express train in 4 hours   10x = 4 x 90 or x =36.   So, speed of goods train = 36kmph.   Ans: 36 kmph
<result>B</result>
A goods train leaves a station at a certain time and at a fixed speed. After ^hours, an express train leaves the same station and moves in the same direction at a uniform speed of 90 kmph. This train catches up the goods train in 4 hours. Find the speed of the goods train.