Solved UPSC CDS/OTA Question
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Q · Boat and StreamModerate · 45s
A boat goes 30 km downstream in 2 h and the same distance upstream in 5 h. Find the speed of the stream.
TopicBoat and Stream
Question Typemultiple choice
DifficultyModerate
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
u+v = 15.0, u-v = 6.0 ⇒ v = 4.5 km/h.
Final Answer: Option B — 4.5 km/h