You have steamed 491 miles at 20 knots and burning 568 barrels of fuel per day. You must decrease your consumption to 265 barrels per day with 313 miles left in your voyage. What must you reduce your speed (kts) to in order to burn this amount of fuel?

Correct Answer: Option A — 17.1

Fuel consumption principles outlined in Bowditch dictate that power and consumption vary cubically with speed. Factoring initial conditions of 20 knots and 568 barrels with the target 265 barrels over remaining distance establishes a required reduced speed of 17.1 knots.