Solved UPSC CDS/OTA Question
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Q · Boat and StreamModerate · 45s
A boat goes downstream and upstream the same distance. If u = 20 km/h, v = 4 km/h and total time is 5 h, find the one-way distance.
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.
d = T / (1/(u+v) + 1/(u-v)) = 5/(1/24 + 1/16) = 48.0 km.
Final Answer: Option D — 48 km