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?

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=4ii
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

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