You are reading the draft marks. 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?
A. 9'-10"
B. 9'-06"
C. 9'-04"
D. 9'-02"
A. 9'-10"
B. 9'-06"
C. 9'-04"
D. 9'-02"
The question has the drafts in feet and inches. Part of the question is to see if you can read draft marks in feet and inches, the other part is to see if you can calculate the mean or "average draft". Keep in mind if you are averaging forward and after drafts the mean draft will not be at midships unless the drafts are at the forward or after perpendiculars.
ReplyDeleteBecause this is the age of calculators it is OK to do the calculation in decimal fractions of an inch. I also suggest you actually sketch the draft mark to make sure you are reading the question correctly.
Forward Draft = 9.5 - 2/12 = 9.5 - 0.167 = 9.333 ft or 9'-04'
After Draft = 10.0 - 4/12 = 10.0 - 0.333 = 9.667 feet or 9'-08"
Mean Draft = 9.333 + 9.667 / 2 = 19 / 2 = 9.5 feet or 9'-06"
The correct answer is Choice B.
Yes I agree , B
ReplyDeleteBRAVO !
ReplyDelete