Solved IB ACIO Question
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Q · Arithmetical Reasoningmedium · 45s
Boat covers 30 km upstream and 36 km downstream in 6 hours. Speed of water 2 km/h. Find boat’s speed in still water.
TopicArithmetical Reasoning
Question Typemultiple choice
Difficultymedium
Marking+1 / −0.25
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Let speed=x; upstream=x–2; downstream=x+2; (30/(x–2)) + (36/(x+2))=6; solve x=10.
Final Answer: Option B — 10 km/h