(A) 8 Km/h
(B) 9 Km/h
(C) 10 Km/h
(D) 15 Km/h
Correct Option is: C
Let ‘x’ be the speed of the boat in still water
Let ‘y’ be the speed of the current.
Pedal boat will travel downstream at (x + y)km/hr and upstream (x – y)km/hr
Therefore 14/x +y + 12/ x –y = 3
10.5/(x+y) + 15/(x-y) = 3 ¼ = 13/4
70/(x+y) +60 /(x-y) =15 –ïƒ 1
42 /(x+y) + 60/(x-y) = 13 –ïƒ 2
From 1 and we get,
x+y = 14 ; x-y = 6
Therefore x= 10 ; y = 4
The speed of the pedalboat is 10 km/hr