A train takes 18 seconds to pass completely through a station 162 m long and 15 seconds through another station 120 m long.The length of the train is	Choose the correct choice from the following options.
A) 70 m  B) 80 m  C) 90 m  D) 100m  E) 110m
Let L be the length of the train.   The train covers a distance of (162 + L) in 18 seconds. The rate is then (162 + L)/18.   The train also covers a distance of (120 + L) in 15 seconds. The rate is then (120 + L)/15.   Presumably, the train is traveling at a constant rate. Therefore, set the two rates equal to each other and solve for L.   (162 + L)/18 = (120 + L)/15   i.e. 90   ANSWER:90 m
<result>C</result>
A train takes 18 seconds to pass completely through a station 162 m long and 15 seconds through another station 120 m long.The length of the train is