A boat goes 24 km upstream and 28 km downstream in 6 hours. It goes 30km upstream and 21km downtream in 6.5 hours. Find the speed of the boat in the still water and the speed of stream. Share with your friends Share 23 Sri Lakshmi Divya Sai answered this 55 View Full Answer Ranjith answered this Let speed of boat be x kmph and of the stream be y kmphWhen boat goes upstream, effective speed of boat will be x - y and when boat goes downstream, its speed will be x+y.Case 1 : To travel 24 km upstream, it takes 24/(x-y) hrsTo travel 28 km downstream, it takes 28 / ( x + y ) hrs 24/(x-y) + 28 / ( x + y ) = 6 - - - ( 1 ) Similarly for case 2, we get30/(x-y) + 21 / ( x + y ) = 6.5 - - - ( 2) Solve equations 1 and 2 -15