Question

A boat takes 5 hours more while going back in upstream than in downstream. if the distance between two places is 24 km and the speed of the boat in still water be 5.5 kmph. what must be the speed of boat in still water so that it can row downstream, 24 km in 4 hours

Answer 1

Upstream components

Time upstream = 4 + 5 = 9hrs

Distance upstream = 24km

Speed upstream = 24/9 km/h

Let the speed of the stream be x.

The speed of the boat is :

24/9 + x

Downstream components

Time downstream = 4Hrs

Distance downstream = 24 km

Speed = 24/4 = 6kmph

Speed of the boat = 6 - x

Equating the two :

6 - x = 24/9 + x

54 - 9x = 24 + 9x

54 - 24 = 9x + 9x

30 = 18x

x = 30/18 = 5/3

Speed of boat in still water is thus :

6 - 5/3 = 13/3 km/h

Into decimal :

4.333 Kmph

Answer 2

Answer:

3.5kmph

Explanation:

a)6kmph

b) 3kmph

c) 3.5kmph

d)4kmph

e)2kmph