Concept: Time taken for journey = Arrival time - Departure timeGiven:The departure and arrival time is given in 24hr format.The departure time at Surat is 16:20 hrs on Day 1.The arrival time at Madgaon is 7:35 hrs on Day 2.Distance already covered by train before Surat = 530 km.Distance covered by train till Madgaon = 1509 kmExplanation:Distance between Surat and Madgaon = Distance covered till Madgaon - Distance covered before Surat. = 1509 - 530 km = 979 kmTime taken between Day 1, 16:20 hrs to Day 2, 4:20 hrs = 12 hrsTime taken between Day 2, 4:20 hrs to Day 2, 7:20 hrs = 3 hrs.Time taken between Day 2, 7:20 hrs to Day 2, 7:35 hrs = 15 minTotal time taken to cover the distance between Surat and Mudgaon = 15 hrs 15 min?Thus, the distance between Surat and Madgaon is 979 km, and the time taken to cover this distance by the train is 15 hours 15 minutes.