Question

a motor boat whose speed is 20km/hr in still water ,takes 1 more to go upstream than downstream to the same spot . find the speed of the stream? ​

Answer 1

Answer:

Let, the speed of the stream be x km/hr

Speed of boat in still water =20 km/hr

∴Speed of boat with downstream 20+x km/hr

∴ Speed of boat with upstream 20−x km/hr

see in image

Either, x=4 or x=−100

∵ Speed cannot be negative ∴x=4 km/hr is considered.

∴ the speed of the stream =4 km/hr