Have you ever come across a multistage cache where you gathered numbers from the wild and plugged them into the blanks to complete the coordinates to the final stage? Of course you have. Have you ever come across one where you were required to do some math and the same number might be used multiple times? Many times these types of puzzles are used because the required number is not found at the locations the hider wanted to highlight. The problem, though, is this technique generally creates a puzzle that is easier to extrapolate without visiting all of the stages. Often the reason it is so easy is because you only have to figure out a single digit.

We've completed many caches this way.

This tool serves as an aid to create a fill-in-the-blank puzzle that is a bit harder to work around and foil. It involves multiplying a series of numbers together to get an eight digit number which you then rearrange to complete the coordinate pair. It is easy to complete directly in the field especially with a calculator and has a bit of a built error checking mechanism as the result has to be 8 digits.

Multiplying these numbers together is very easy. The problem is getting those numbers to begin with.

This particular technique involves starting with your 8 digits, and considering keeping them in order would severely limit the outcome, rearrange them into another 8 digit number, and then finally, finding its factors. (Factors being the numbers which when multiplied together results in the original number.)

To use the tool, extract the four least significant digits in both set of numbers of your coordinates. Example:

33° 12.345
80° 16.789
These are highlighted in red in the example above.

Take these numbers and enter them into the tool. (They can be in any order as we are going to scramble them anyway.) Click submit.

You will be presented with your numbers scrambled and the prime numbers that when multiplied together will result in that number. Using our example above, we might be presented with:

57943628 : 2 × 2 × 37 × 53 × 83 × 89

We would create a puzzle so the finder would need the numbers 2, 2, 37, 53, 83, and 89. Note that some results are multiple digits thus making it harder to guess.

We could combine some of the numbers if we had to. Multiplying any of the numbers together will not change the result, so we could combine (multiply) 2 and 37 to use 74 because we have 1974 on a memorial.

We could also adjust a number. Say we had the year 1886 on a memorial. We could use "Find 18XX. XX plus 3 = ZZ" to use the 89 in the above example.

Most likely you might want to let the seekers know they could benefit from a basic calculator to multiply all of these numbers together, but the beauty is it can still be done long hand.

However you do it guide the seeker to come up with the 8 digit number.

Our coordinates template has a familar look:
33° 1A.BCD
88° 1E.FGH

but because the number pattern will likely be scrambled so must the letter pattern:
_ _ _ _ _ _ _ _
D F H C B E A G

Filled in our example will look like this:
5 7 9 4 3 6 2 8
D F H C B E A G

The seeker would then reconstruct the coordinates for the final stage.

Try to make the least significant numbers of the coordinates the most significant of the 8 digit number. While this is not always possible, it does create a harder to guess puzzle. The being a slight change in one of the larger numbers or combinations will have less effect on the least significant numbers of the result. If that is also the same as the least significant of the coordinates then the result could be wrong but close the actual location. Wrong digits in the more significant numbers will result it a much higher real-world error.

Find your final first and use the tool. Print out the page to take with you on your scouting trips.

You can place your numbers in the wild, too!

This techinque can replace the linear multicache where you guide the seeker from place to place. The problem with linear stages is they can be skipped. All one really needs is the last intermediate stage and they then have the coordinates to the final. This technique pretty forces the seeker to go to each stage.

This technique is highly susceptible to missing stages. Make sure they are durable as one missing stage can stop the hunt completely.

WARNING: Checksums make this technique easier to crack.

Fewer, larger numbers are harder to guess than more, smaller numbers making it harder to crack.