Chart Navigation & Plotting · Distance, Speed & Time
A vessel makes good 12 knots. How far does it travel in 20 minutes?
- A2.0 nautical miles
- B3.0 nautical miles
- C4.0 nautical miles✓ Correct
- D6.0 nautical miles
Explanation
Distance = speed × time. 20 minutes is one-third of an hour, so 12 kn × (20/60) = 4.0 NM. The relationship 60D = S × T (with T in minutes) gives the same result: D = (12 × 20)/60 = 4.
Authority: Bowditch, Pub. No. 9 (speed-time-distance)
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