You are reading the draft marks as shown in illustration D032DG. The top 2 inches of the 9 forward is visible above the water level, and the water level is four inches below the 10 aft. What is the mean draft?
• Each large number on the draft scale represents whole feet, with the space between numbers equal to 1 foot (12 inches). • The problem gives how many inches the waterline is above or below a number, so you must convert that to a draft in feet and inches for forward and aft. • The mean draft is the average of the forward and aft drafts: add them together and divide by 2.
• How many inches below the bottom, middle, or top of the "9" is the waterline if only the top 2 inches of the 9 are showing forward? Draw or visualize the 1‑foot space and mark the waterline. • If the water level is 4 inches below the 10 aft, how many inches is that above the 9 aft? What is the aft draft in feet and inches? • Once you have forward and aft drafts in inches, what is their average, and which choice matches that average when converted back to feet and inches?
• Be sure you know where on the numeral the foot value is measured (bottom of the number, not the top). • Convert all partial feet to inches before averaging, then convert back to feet and inches at the end. • Double‑check that your forward draft is less than 9' (since part of the 9 is showing) and your aft draft is more than 9' (since you are below the 10).
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