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Question

How do you solve this? I'd appreciate any help.

Thanks.

At noon, ship A is 50 nautical miles due west of ship B. Ship A is sailing west at 25 knots and ship B is sailing north at 24 knots. How fast (in knots) is the distance between the ships changing at 7 PM? (Note: 1 knot is a speed of 1 nautical mile per hour.)

Answer 1

I'm not sure, but by using a 90 degree angle and ruler  using 1/4' hashes as knots measuring ship to ship and multiply that by 7, I came up with 241.5 knots distance.