Solved UPSC CDS/OTA Question
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Q · Boat and StreamModerate · 45s
A boat travels 36 km downstream and returns upstream. If u = 12 km/h and v = 4 km/h, find the total time.
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.
Time = d/(u+v) + d/(u-v) = 36/16 + 36/8 = 2.25 + 4.5 = 6.75 h.
Final Answer: Option A — 6.75 h