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June 18

What's the distance?

A boat take 23 min 35 secs to complete a course at average speed of 23.21 knots. How far has it travelled in miles, and how far in metres? Moriori (talk) 02:53, 18 June 2017 (UTC)[reply]

@Moriori:

Please do your own homework.

Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. --Jasper Deng (talk) 03:02, 18 June 2017 (UTC)[reply]

(Yes, I know you've probably asked questions here before, but I firmly believe we shouldn't work out solutions without the asker first trying; knots = nautical mile/s).--Jasper Deng (talk) 03:03, 18 June 2017 (UTC)[reply]

Your apology is accepted. The figures I gave came from an actual America's Cup race this morning. I casually asked a couple of friends what the distance travelled would be, and got two different answers. Eureka, I know, I said, I'll ask at the wiki maths reference section which has all sorts of boffins involved. Unfriendly testy ones too I see. Moriori (talk) 03:19, 18 June 2017 (UTC)[reply]

Well, if you will use the same sort of wording that a homework problem would, it shouldn't be surprising if people think that's what you're doing!

A nautical mile is 1852 meters, but a knot is one nautical mile per hour (3600 seconds), not per second as Jasper said. So the distance in meters is 1852 × 23.21 × (23×60 + 35) / 3600 = 16,895 m, which should be rounded to 16,900 m since the inputs only have 4 significant digits. Now a mile is 1609.344 m; so divide by that number and you get 10.50 miles. --76.71.5.114 (talk) 06:26, 18 June 2017 (UTC)[reply]

My bad, I'm so used to using seconds for time.--Jasper Deng (talk) 07:44, 18 June 2017 (UTC)[reply]

Reasonableness check - a nautical mile is a bit longer than a statute mile. So we have a boat travelling at a little more than 20 mph for a little less than half an hour. So ballpark answer is 10 miles. Gandalf61 (talk) 09:45, 19 June 2017 (UTC)[reply]