🔍 Key Concepts

• Fuel consumption vs. speed – how fuel use changes when speed changes • Relationship between speed and engine power – is it linear or does it increase faster than speed? • Using ratios/proportions correctly when one quantity depends on another (like speed or speed cubed)

💭 Think About

• If fuel consumption is tied to required power, and required power does not increase in a straight line with speed, how should you adjust the 216 bbl/day figure when going from 15.0 to 17.5 knots? • Compute the ratio between the two speeds; how can you use that ratio (or its square or cube) to estimate the new fuel consumption? • Once you apply the proper relationship between speed and fuel consumption, which answer choice is closest to the calculated value?

✅ Before You Answer

• Carefully compute the speed ratio: 17.5 ÷ 15.0 and keep enough decimal places for accuracy • Decide whether to use the speed ratio, its square, or its cube when scaling fuel consumption, based on how resistance/power change with speed for displacement vessels • After scaling 216 bbl/day by the appropriate factor, check which option is numerically closest to your result