Question

Pratap Puri rowed 14 miles down a river in 2 ​hours, but the return trip took him 3 and one half hours. Find the rate Pratap can row in still water and find the rate of the current. Let x equals rate Pratap can row in still water and y equals rate of the current. What is the rate that Pratap rows in still​ water?

Answer 1

speed of current is 1.5 mi/hr

Answer:

let the rate in still water be x and rate of the current be y.

speed down the river is:

speed=distance/time

speed=14/2=7 mi/h

speed up the river is:

speed=(14)/(3.5)=4 mi/hr

thus total speed downstream and upstream will be:

x+y=7...i

x-y=4.......ii

adding the above equations i and ii we get:

2x=11

x=5.5 mi/hr

thus

y=5-5.5=1.5 mi/r

thus the speed in still waters is 5.5 mi/hr

speed of current is 1.5 mi/hr