Question

17. The speed of a stream is 2 km/h. A boat travels between two ports downstream in 4 hours and upstream in 6 hours. Find the speed of the boat and also the distance covered.​

Answer 1

Step-by-step explanation:

Correct option is

A

80 km

Let speed of the streamer in still water= x km/hr

Speed of downstream =(x+2)km/hr

Distance between the ports =4(x+2)km.... (i)

Speed of upstream =(x-2)km/hr

Distance between the ports =5(x−2)km....(ii)

from Equation (i) and (ii)

4(x+2)=5(x−2)

4x+8=5x−10

x=18

∴ Distance between two ports =4(x+2)

=4(18+2)km=80 km