Haryana Police Constable Model Paper 5

Let the speed of the current be x and the man’s speed be y km/hr.
$\mathrm{Distance}=\mathrm{speed}\times \mathrm{time}$
$16=\left(\mathrm{x}+\mathrm{y}\right)\times 4$
$\Rightarrow \mathrm{x}+\mathrm{y}=4$ ----(1)
$6=\left(\mathrm{y}-\mathrm{x}\right)\times 2$
$\Rightarrow -\mathrm{x}+\mathrm{y}=3$ ----(2)
Adding (1) and (2)
$\Rightarrow 2\mathrm{y}=7$
$\Rightarrow \mathrm{y}=3.5$
From (1)
$\therefore \mathrm{x}=4\mathit{–}3.5=0.5\frac{\mathrm{km}}{\mathrm{hr}}$