Chart Navigation & Plotting · Speed-Time-Distance — Speed
A vessel runs 60 NM between fixes taken 4 hours apart. What is the speed over the ground?
- A16 knots
- B12 knots
- C15 knots✓ Correct
- D240 knots
Explanation
Speed = distance ÷ time = 60 NM ÷ 4 h = 15 knots.
Authority: Bowditch (Pub. No. 9), Speed-Time-Distance
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