Pennies in Boxes

[undecim]

(Warning: May contain lateral thinking)

You (a US resident) receive an interesting package delivered to your back yard. It is an enormous, cubical, cardboard box, with an internal side length of 10m.

You open the box, and find that it is completely filled with smaller cubical cardboard boxes, each with an external side length of 0.02m. These smaller boxes aren't simple boxes, and are actually quite a bit more complicated to open. They are strange patterns of sturdy, interlocking cardboard, and no two boxes seem to be the same. Even using a knife, it takes you about two minutes to reach the contents of one box: a single penny (0.01 USD). You open a few more, and find the same thing.

Assuming that the rest of the boxes are like this, the sum of the contents of the small boxes is worth $1.25 million. You want this money in your bank account, where you can use it with your debit card.

Manually removing each penny would give you $0.30/hour... maybe $0.50 if you tried hard, but still a fraction of federal minimum wage ($7.25/h). Simply burning the cardboard would violate local bonfire laws, as the flames would be over 30 feet in the air. (It would also pose a danger to nearby buildings, and as mward has pointed out, melt most of the pennies.)

You call your bank and find out that they will take the pennies and deposit them to your account, as long as you can bring only pennies, with no additional packaging or debris. They won't even require you to roll them, like most banks do.

You can carry about $200 worth of pennies (50 kg) at a time. You can also rent a truck that can carry $4000 worth of pennies (1,000 kg), and the bank is only 15 minutes away. In other words, it will be more than worth your time to haul a giant pile of pennies to the bank.... If you can just get the cardboard out of the way.

[HonoreDB]

Spoiler:

First thought is to find an acid that reacts with cardboard but not metal. I know you can clean pennies with acid.

[douglasm]

Spoiler:

Sell the cardboard to a recycling company?

[ConMan]

Spoiler:

Hire some boy scouts/girl guides/other youths interested in doing some manual work for a share of the profit?

[dudiobugtron]

Here are some potential ideas - I don't know how well they'd really work though!

Spoiler:

A) Get a horde of termites (or other animals which eat cardboard but not pennies). I imagine you'd need a lot of termites though, enough to probably eat away at the foundations of your house after they've finished with the cardboard! This would also be tricky because there would almost certainly be some cardboard left in between the pennies, especially near the bottom.

B) Erect a swimming pool around the box, and cover it entirely with water (thoroughly soaking it too, hopefully). I'm not sure exactly what you'd do after that, but it would make the boxes much easier to dismantle. Maybe you could 'sift' for pennies like they do with gold.
If only pennies were magnetic!

C) Leave the cardboard exposed to the elements and wait for it to biodegrade.

D) Do any of the above things to the pennies, but in more manageable piles instead of all at once. You could even burn them. Eg: use a spade or something to get a pile of pennies into an incinerator, or a termite mound, or a swimming pool etc...

E) Study the box designs and use them to create a host of fiendish puzzles, which you can sell for money. Or, simply sell the individual boxes for money, with the penny still inside.

F) Charge admission to see it (and get a souvenir penny).

G) Sell the whole box to Samsung.

Cool idea for a puzzle btw. I hate to think how much time and money it cost to create that package in the first place!

[imyourfoot]

Given the lateral thinking disclaimer and the fact that the OP doesn't explicitly say so:

1) Are we required to get the pennies to the bank in an undamaged state? Or would a solution like melting the boxes down, centrifuging the results, then selling the resulting metal work?

2) Are we limited to tools/resources that an average person could acquire without much trouble?

[mward]

Sell the cardboard to a recycling company?

Your cube has a volume of 1,000 cubic meters. Cardboard has a density of 689 kg per cubic meter, (http://www.aqua-calc.com/page/density-table/substance/Cardboard) so assuming that the cube is pretty much solid cardboard it would weigh about 689 tonnes. Cardboard recycling prices vary from £80 to £124 per tonne, (http://www.letsrecycle.com/prices/waste%20paper) so the cardboard is only worth about £70,000 or about $100,000.

The metal in the pennies is more valuable: 125,000,000 pennies at 2.5 grams of 97.5% zinc per penny is over 300 tonnes of zinc, which is worth about $560,000. However, it is illegal to melt down pennies and nickles:
http://www.usatoday.com/money/2006-12-14-melting-ban-usat_x.htm

[undecim]

Given the lateral thinking disclaimer and the fact that the OP doesn't explicitly say so:

1) Are we required to get the pennies to the bank in an undamaged state? Or would a solution like melting the boxes down, centrifuging the results, then selling the resulting metal work?

2) Are we limited to tools/resources that an average person could acquire without much trouble?

Like you said, I didn't explicitly say you couldn't do anything, except for burning, and I think any solution would be interesting.

For the bank to take the money, it must obviously be legal tender... Though I having trouble figuring out at what point of damage a penny ceases to be legal (EDIT: This ehow article has some good info, with references; short story: They must be identifiable as pennies), I'd like to point out that it is against U.S. law to intentionally damage U.S. currency. So if you do something like that, you'll need to do it secretly, which will be pretty hard, assuming that your neighbors won't ignore a cardboard box that is taller than a 2-story house.

Feel free to bring in any tools and resources you want, but ideally the total cost of using the resources should be less than $1.25M (unless you can make more than the nominal $1.25M)

Spoiler:

E) Study the box designs and use them to create a host of fiendish puzzles, which you can sell for money. Or, simply sell the individual boxes for money, with the penny still inside.

F) Charge admission to see it (and get a souvenir penny).

Spoiler:

Wow, the potential for profit there is pretty big. sell them at $1 each, and get $125M. Or at $8 each and become a billionaire. I think you could get some news coverage to make them sell really fast.

[balr]

One word:

Spoiler:

Crowdscourcing.

Get other people do do the work for you, and have them pay you do it it.

Rent access to the box at (say) USD5 per hour. Let the extractors take whatever cardboard and pennies they can extract.

Sell them knives, coffee, charge for bathroom access, charge high rates for them to attend seminars with your more successful extractors. Fuel speculation by refusing to deny rumors of historical, rare and valuable coins in there (just say you don't know; that's the simple truth).

That's a type of Disneyified crowdsourcing. You'll make millions.

[elasto]

Spoiler:

My answer repeats earlier ones really:
- Dig a pit in your garden of manageable size - eg. 5m x 5m x 2m
- Line it with some protective material - eg. pool liner
- Fill it with small boxes to a depth of a meter or so
- Add something that will be self-sustaining and cause the cardboard to degrade rapidy but that can't escape the pit - eg. bacteria/termites/mice or just plain water, whatever works
- As the cardboard degrades add more boxes until you run out
- Then scoop out the pennies, hose them down and ship them off

As an alternative, I assume that with $1.25m at stake you could build some sort of smokeless furnace system for a couple thousand dollars at most that could burn off the cardboard. Dunno if that is in the spirit of the puzzle, though.

I have a question though: I'm wondering if we should read anything in to the fact the puzzle singles out that you are specifically a US resident - eg. is there some solution that would work for a US resident but wouldn't work for a UK one, say? Like is there some obscure Federal law you can twist to your advantage?

[dudiobugtron]

I have a question though: I'm wondering if we should read anything in to the fact the puzzle singles out that you are specifically a US resident - eg. is there some solution that would work for a US resident but wouldn't work for a UK one, say? Like is there some obscure Federal law you can twist to your advantage?

I imagine the main difference is the size of their pennies. Or, depending on the country, the existence of pennies at all.

[undecim]

Spoiler:

My answer repeats earlier ones really:
- Dig a pit in your garden of manageable size - eg. 5m x 5m x 2m
- Line it with some protective material - eg. pool liner
- Fill it with small boxes to a depth of a meter or so
- Add something that will be self-sustaining and cause the cardboard to degrade rapidy but that can't escape the pit - eg. bacteria/termites/mice or just plain water, whatever works
- As the cardboard degrades add more boxes until you run out
- Then scoop out the pennies, hose them down and ship them off

As an alternative, I assume that with $1.25m at stake you could build some sort of smokeless furnace system for a couple thousand dollars at most that could burn off the cardboard. Dunno if that is in the spirit of the puzzle, though.

I have a question though: I'm wondering if we should read anything in to the fact the puzzle singles out that you are specifically a US resident - eg. is there some solution that would work for a US resident but wouldn't work for a UK one, say? Like is there some obscure Federal law you can twist to your advantage?

I just used "US Resident" so that the puzzle can be consistent. I know what the penny looks like, how they can scale, (heck, I even helped my local school with a "1 million penny drive"), I know what kind of stuff U.S. banks will do for their customers, and I know about the laws there. Generalizing it to every country would have left out details that would have excluded the needs for workarounds, for example, the burn laws, the fact that only a small number of the coins will be magnetic (http://en.wikipedia.org/wiki/1943_steel_cent), that they are under 2cm in diameter, etc, etc. I had no obscure laws in mind.

[Qaanol]

First build walls around the four sides, and put a roof on it. Something simple like plywood on a frame of 2×4s will work. Then:

Spoiler:

Use a laser to cut through the cardboard, and a leafblower to disperse the chaff.

[HonoreDB]

Spoiler:

My girlfriend's solution: transport the box to a remote area, put down a flame resistant tarp, and burn it.

[mward]

All those who are considering solutions which involve setting fire to the cardboard should take note of the following:

• Cardboard burns at 427 degrees C
• The melting point of zinc (the main constituent of pennies) is 419.53 degrees C

Selling the boxes seems like the best bet so far: especially if you can somehow make them into the next fashion craze!

[Moose Anus]

Spoiler:

Start a bank, allowing people to deposit pennies in cardboard boxes as currency. When someone makes a deposit, they'll probably give you a penny in an easy to open box. When they make a withdrawal, you can give them the hard to open boxes.

[undecim]

Spoiler:

Start a bank, allowing people to deposit pennies in cardboard boxes as currency. When someone makes a deposit, they'll probably give you a penny in an easy to open box. When they make a withdrawal, you can give them the hard to open boxes.

Any ideas on driving adoption rate of your new currency?

[Moose Anus]

Spoiler:

Start a bank, allowing people to deposit pennies in cardboard boxes as currency. When someone makes a deposit, they'll probably give you a penny in an easy to open box. When they make a withdrawal, you can give them the hard to open boxes.

Any ideas on driving adoption rate of your new currency?

Uh, savings pays 2% APR.

[dudiobugtron]

Spoiler:

My girlfriend's solution: transport the box to a remote area, put down a flame resistant tarp, and burn it.

Spoiler:

How do you transport it? It's 10mx10mx10m !! I'm not saying it's impossible, it just seems like it would be rather expensive to do.

[Barstro]

Spoiler:

How about something along the line of a cotton gin? Gnarled fingers and reach into the cardboard/penny mix and pull out bits of cardboard, leaving pennies behind. Not cost effective, though. Also, it might need a decent soaking and drying to make the cardboard the correct consistency.

or

Spoiler:

second idea already proposed at least once.

[mike-l]

I'd like to point out that it is against U.S. law to intentionally damage U.S. currency. So if you do something like that, you'll need to do it secretly, which will be pretty hard, assuming that your neighbors won't ignore a cardboard box that is taller than a 2-story house.

It's actually OK to deface pennies, as long as you aren't using it as tender afterwards. In fact, in lots of the (government) museums in DC there are penny squishing machines that will press pennies flat with some design on them.

Not that this helps the problem, as you do want to use the pennies as tender. Though maybe you could sell them as jewellery instead.

[Adam H]

Spoiler:

What about some sort of centrifuge submerged (partially?) in water? After the cardboard becomes soggy enough to fall apart, it would float to the middle while the pennies sink to the sides... er, I guess sopping cardboard wouldn't be that buoyant. Maybe salt water? Yeah, I don't know science.

Well I guess I'm off to go put some cardboard boxes in my washing machine and see what happens. (Not really)

[casualevils]

Spoiler:

Why not just burn the boxes in smaller groups? Fill a fire pit with boxes, burn, scoop out pennies, repeat.

[elasto]

I'm assuming there's an 'official' answer to this puzzle from the opening disclaimer 'warning: may contain lateral thinking', right?

And I further assume that noone has posted the 'correct answer'?

[undecim]

I'm assuming there's an 'official' answer to this puzzle from the opening disclaimer 'warning: may contain lateral thinking', right?

And I further assume that noone has posted the 'correct answer'?

Lateral thinking problems don't typically have a single correct answer. I had no specific answer in mind when posting.

[Moose Anus]

1) Buy some arcade games that take pennies instead of quarters.
2) Advertize that you can just get a penny at the arcade itself, in a handy box.
3) Profit.

[Xias]

Run for federal office, and push a bill to eliminate pennies from circulation. Wait some amount of time for the majority of pennies to disappear and the collector value of pennies to rise to a point where opening the boxes would be profitable.

[dudiobugtron]

Wait some amount of time for the majority of pennies to disappear and the collector value of pennies to rise to a point where opening the boxes would be profitable.

That might take some time, given the number of pennies in circulation currently!:
http://www.kokogiak.com/megapenny/twelve.asp

[Adacore]

Build a fence around it, and wait. Cardboard normally completely biodegrades in a few months, if my googling is accurate. It's probably slower for a 10x10 cube of cardboard, but shouldn't be that much slower. There are probably things you can do to speed it along, too, like spray it with a hose every few days, and break it down into smaller chunks. So if you wait for a year you'll have a huge pile of mulch full of pennies. At that point, just sieve the pennies out.

EDIT: Might need to do some research to work out if the pennies will be sufficiently degraded to no longer be legal tender after that. I'd think they'd be shabby, but ok, but I'm not certain.

[rockachu2]

Spoiler:

Dump the whole thing into hot water and add acetone. Now you have acetone, water, sugar, and pennies.
Note: Acetone is lightly toxic, but is not currently regarded as being carcinogenic or a neurotoxin. It isn't environmentally friendly, but hey.

[freakish777]

In fact, in lots of the (government) museums in DC there are penny squishing machines that will press pennies flat with some design on them.

All the more reason to turn your big box(es) of pennies into an attraction that charges admission (and sells boxes at the gift shop? after opening said box they can put their penny into your flattening machine as a commemoration of their visit).

[lord carnifex]

Spoiler:

Similar to the biodegrade option above, spray the cardboard down repeatedly, allowing it to dry each time, iuntil it starts to get flaky and break apart. Then shovel the resulting mess into a wood chipper*. Catch the resulting mass in 55 gallon drums. Proceed to agitate the drums so that the denser pennies fall to the bottom like popcorn kernels in a bowl of popcorn. Shovel off the cardboard chips and sell to as mulch or insulation for cheap houses. Pour out the substrate of pennies. Confusion. Profit.

* I haven't done any reality testing on this. You'll want a chipper with widely spaced enough blades and little torque, so it doesn't deface the pennies themselves, but operating at high enough speeds that it catches the cardboard and flakes it off. It's possible that an industrial document shredder would work better.

[Felix Griffin]

Spoiler:

Concentrtated sulfuric acid doesn't damage copper, does it? And it eats through cardboard very, very well, as my high school bio teacher demonstrated to us.

If it does, you could always precipitate it out afterwards and sell it. You didn't melt the pennies down (need to check on the law's wording), after all.

[elasto]

Dunno why we're all using spoiler tags given that there's no actual answer to spoil! Anyone's guess is basically as good as anyone else's!

[jestingrabbit]

Spoiler:

Concentrtated sulfuric acid doesn't damage copper, does it? And it eats through cardboard very, very well, as my high school bio teacher demonstrated to us.

If it does, you could always precipitate it out afterwards and sell it. You didn't melt the pennies down (need to check on the law's wording), after all.

I'm pretty sure that copper + sulfuric acid -> copper sulfate + water + heat, and copper sulfate is relatively valueless.

[dudiobugtron]

I'm pretty sure that copper + sulfuric acid -> copper sulfate + water + heat, and copper sulfate is relatively valueless.

I guess if you were running low on water and heat though it might be useful.

[ThirdParty]

Here's an inefficient brute-force solution that recovers about a third of the value of the pennies without using any chemistry:

Spoiler:

Hire an intermodal shipping company to transport about 1000 cubic meters of little boxes from your back yard to Cambodia. Estimated cost: $25,000.
Hire 4 million man-hours of unskilled labor in Cambodia, to unpack the little boxes. Estimated cost: $700,000.
Hire the intermodal shipping company again, to transport the pennies from Cambodia back to your bank. Estimated cost: $5,000.
Deposit the pennies. Estimated revenue: $1,250,000.
Cambodian taxes: 20% of profit.
Estimated net profit: $415,000.
The satisfaction of being a "job creator": priceless.

[freakish777]

Spoiler:

Concentrtated sulfuric acid doesn't damage copper, does it? And it eats through cardboard very, very well, as my high school bio teacher demonstrated to us.

If it does, you could always precipitate it out afterwards and sell it. You didn't melt the pennies down (need to check on the law's wording), after all.

Good luck getting a hold of large amounts of sulfuric acid without arousing the suspicion of the FBI...

[undecim]

Good luck getting a hold of large amounts of sulfuric acid without arousing the suspicion of the FBI...

I'm sure the box itself has already accomplished this.

[markdennehy]

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