# Easy Time, Speed & Distance Solved QuestionAptitude Discussion

 Q. A boat covers a distance of 30 km downstream in 2 hour while it takes 6 hour to cover the same distance upstream. What is the speed of the boat in km/hr
 ✖ A. 5 ✖ B. 7.5 ✔ C. 10 ✖ D. 12

Solution:
Option(C) is correct

Let $b$ and $s$ be the speed of boat and stream respectively.

As per the given conditions:

$\dfrac{30}{b+s}=2$-----(1)

$\dfrac{30}{b-s}=6$

From eq (i) and (ii):

$s = 5$ and $b$ = 10 km/hr