The Delhi Express runs @ 144 kilometers per hours and it reaches destination 20 minute ahead of schedule. If it averages 100 km/hour, it reaches 24 minute behind schedule. What is the average speed it should maintain in order to reach the destination on schedule?	Choose the correct answer:
A) 250
B) 240
C) 230
D) 245
E) 235
If the destination is D kilometer and the speed in order to reach on schedule is S km/hour,   the time taken to reach on schedule is D/S hours   Thus we get two equations:   D/144 = D/S - 1/3 and   D/100 = D/S + 2/5 and   Subtracting the first equation from the second we get : 44D/14400 = 11/15   Thus D = 14400 x 11/ 44 x 15 = 240   ANSWER:240
<result>B</result>
The Delhi Express runs @ 144 kilometers per hours and it reaches destination 20 minute ahead of schedule. If it averages 100 km/hour, it reaches 24 minute behind schedule. What is the average speed it should maintain in order to reach the destination on schedule?