One of the benefits of membership in geocaching.com is that you have the option of receiving notification of new caches in your area by entering the ZIP CODE (it's not really a code is it?) or by simply searching using the ZIP CODE. Among other things, this information includes the distance to those new caches from some datum location (that is referred to as Ground Zero or GZ). In order to calculate these distances, geocaching.com has established this datum location in each city/town from which to make these measurements. (Any idea on how GZ is established? Neither do I.)
To find this cache you must first find the ZIP CODE for where the posted (dummy) coordinates are located. Second, find the GZ coordinates for that ZIP CODE.
Once you have GZ, subtract 0.430 minutes from the north coordinate and add 3.008 minutes to the west coordinate.
(And if Geochecker doesn't like those numbers, try zip-codes.com for their lat, long, and subtract 0.356' from north and add 2.487' to west. Finally, if nothing works, shoot me an e-mail.)
You can check your answers for this puzzle on Geochecker.com.
Here's what you don't need: 1) To triangulate anything, 2) Google Earth, 3) Geometry.
UPDATE 1-24-11 Centroid shifted, so there are now new numbers (above) to add to the geocaching.com centroid to get the cache coordinates.
UPDATE 4-9-11 I didn't think things would be shifting so fast - centroid has changed again so there are again new numbers to use to get the cache coordinates.
UPDATE 5-4-11 I noticed a change after the latest site upgrade, so the adjustment numbers (above) are changed again.
Update 1-23-12 Changed again (and I checked them just a couple of weeks ago!)