At the posted coordinates you will find a sign - us it for clues to the final.
The final cache is at:
N39 15.650 W84 32.0AB
A = the number of vertical fence posts there is on the fence keeping you from falling into the sinkhole
Q = on the diagrams at the bottom of the sign there are curved arrows showing the the water entering the soil from the air. How many arrows are there?
B = 2(Q)
Sum check A+B=11
Tha cache is a preform down in a stump 10 feet off the trail. Look for the twig "handle" to make the grab.