BCS : A left at 10 km per hour and B at 15 km per hour at the same time from the same place towards Rajshahi. A reached Rajshahi at 10.10 minutes and B at 9.40 minutes. What is the distance of Rajshahi from the place of departure in km? [11th BCS] (a) 15 (b) 25 (c) 20 (d) 28 Answer : (a) 15