Speed and Time 1 - Answer

View the Question Speed and Time 1 

5 kms/hr

 Let the speed of boat be x and speed of river be y.

 Speed upstream = x - y
Speed downstream = x + y

 Also x - y +5 = x + y.
 So y = 2.5 kms/hr

and 3(x - y) = x + y
 -> 3x - 3y = x + y
 -> 2x = 4y
 -> x= 2y = 5kms/hr