CAT 2025 Slot 2 QA Question 10: Rita and Sneha can row a boat at 5 km/h and 6 km/h in still water, respectively. In a river flowing with a constant velocity, Sneha takes 48 minutes more to row 14 km upstream than to row the same dis

Question

Rita and Sneha can row a boat at 5 km/h and 6 km/h in still water, respectively. In a river flowing with a constant velocity, Sneha takes 48 minutes more to row 14 km upstream than to row the same dis

Accepted Answer

Let the speed of the stream be $v$ km/h.

For Sneha, upstream speed $= 6-v$ and downstream speed $= 6+v$.
$\dfrac{14}{6-v} - \dfrac{14}{6+v} = \dfrac{48}{60} = \dfrac{4}{5}$
$\Rightarrow \dfrac{28 v}{36-v^2} = \dfrac{4}{5}$
$\Rightarrow v^2 + 35v - 36 = 0$
$\Rightarrow v = 1$, since speed is positiv