There are five Olympic Rings (Blue, Yellow, Black, Green and Red). Each travel bug has two tags attached which have some letters and numbers on them.
Update 05-Mar-2024: Some of the original TB's have gone missing over the years. I have released copies for these but rather than having tags attached the necessary information is on the back.
You need to find each of the five travel bugs and work out the following:
a = Red K+K
b = Green F+F
c = Yellow G+G
d = Black H+H
e = Blue D+D
f = Green K+K
g = Black E+E
h = Yellow E+E
i = Red B+B
j = Blue J+J
Here "Red K+K" simply means that you need to add together the numbers associated with the two letter K's on the Red Olympic Ring travel bug. You do the same thing with all the others. It might sound complicated but don't worry, it will be really obvious when you see it.
The cache is hidden at N51 x/1000 W0 y/1000
where
x = a*(b+c)*(d+e+f)
y = 3*(x + (g*h*(i-j)))