At the 2012 Summer Olympics in London, Michael Phelps' last individual race was the 100m butterfly. He won the gold medal with a time of 51.21 seconds.
What was Phelps' average speed over this race?
Let's say he starts at the posted coordinates and swims at that pace for 27 minutes, 20.8764 seconds at bearing 44.043 degrees. Where would he end up?
Assuming he can also swim on land, he'd be at the actual cache location.
You can check your answers for this puzzle on GeoChecker.com.