The posted coordinates will bring you to one B Train. Another set of coordinates are hidden here somewhere, and to find them, you'll have to wait for a train to come through.
When a train comes through, count the number of times the red lights flash on the tallest set of lights from where you stand, during the space of time from when the bells stop ringing until the lights stop flashing. That number = A
(If you think the answer is a bit borderline between two numbers, go for the lower one!)
Count the number of those railway flashing lights at this intersection. Count all of them (lights, not pairs of lights). That number = B
S 37° 47.9A2 E 145° 06.(B-1)60
Then, proceed to the new coordinates. It's too far to walk, but a short drive or cycle.
At the new coordinates you will find another B Train or two. A bit smaller this time, and this one isn't going anywhere.
How many large wheels do the locomotives have between them? That number = a
How many small wheels do the locomotives have between them? That number = b
Now insert your answers into these coordinates:
S 37° 47.8(a+3)(a-b+3)
E 145° 06.9(b-1)(a-b)
The cache is a very short walk away. Muggle factor is quite high, so proceed with caution and please ensure the cache is returned safely to its original position.
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