Slashdot Mirror
Making Change
Roland Piquepaille writes "There are mostly four kinds of coins in circulation in the U.S: 1 cent, 5 cents, 10 cents, and 25 cents. But is it the most efficient way to give back change? This Science News article says that a computer scientist has found an answer. "For the current four-denomination system, [Jeffrey Shallit of the University of Waterloo] found that, on average, a change-maker must return 4.70 coins with every transaction. He discovered two sets of four denominations that minimize the transaction cost. The combination of 1 cent, 5 cents, 18 cents, and 25 cents requires only 3.89 coins in change per transaction, as does the combination of 1 cent, 5 cents, 18 cents, and 29 cents." He also found that change could be done more efficiently in Canada with the introduction of an 83-cent coin and in Europe with the addition of a 1.33- or 1.37-Euro coin. Check this column for more details and references." The paper (postscript) is online.
I think the advantage to having a 10-cent piece is that it makes the math easy. Let's face it; can you imagine the average cashier at WalMart giving back 98 cents change with an 18-cent coin?
Swannie
:q!
Are you kidding me?!
... *pause* .... and just stare blankly at the change drawer.
Have you ever gotten a bill for dinner for say $12.50 and you give the cashier $15 saying the tip is included?
You would think 15.00 - 12.50 is doable right?
HELL NO! The cashier pulls out a calculator to do the math so she can write it in for the waiter's tips!!!
If people can't add things like this 18cent coins are out of the question.
Although I would like to hear a cashier go,
"That makes $0.88 change sir." Pick out two quarters then,
"Engineers do the work of man, Physicists do the work of God"
Is it too early in the morning or does this article not make sense? I have never seen an 18 cent piece in circulation n the US...
Eric Aitala
www.f1m.com
Exactly. All you need is a 1 cent coin, and a, er, zero cent coin!
Skiing? Check out The Independant Skiers Portal
"There are mostly four kinds of coins in circulation in the U.S: 1 cent, 5 cents, 18 cents, and 25 cents"
Where is this 18 cent coin? Have I been living under a rock? Are my dimes now worth 18 cents?
Everyone is entitled to their own opinion. It's just that yours is stupid.
I had 18 cents everytime I heard that.
I don't suffer from insanity, I enjoy every minute of it.
I was at a conveinece store yesterday. The price came to $1.37. I tendered $2.12. The cashier's head almost exploded.
Here in Canada the only chance of our coinage being worth 87 cents is if the US keeps up it's foreign policy for another 6 months. (our dollar hasn't been this high in about 7 years)
I went to battle MC Escher but drew a blank
So- you have 7 18-cent coins, Susie gives you 13, and you give Bobbie 3. How many nickels must Daddy give you for your 18-cent coins...?
Then, you get on a train in Boston traveling east at 300 MPH. In 30 minutes, will you really care about how many 18-cent coins you're carrying?
Whew! This water sure is cold!
So getting rid of marketeers would *also* simplify making change? What are we waiting for?!
Trouble making decisions? Just flip for it.
Don't y'all remember the SchoolHouse Rock about counting by 18?
. . .
*taps foot*
Eighteen is a magic number.
Yes it is, it's a magic number.
Somewhere in the ancient, mystic eighteenity
You get eighteen as a magic number.
The past and the present and the future,
Faith and hope and charity,
The heart and the brain and the body
Give you eighteen.
That's a magic number.
18, 36, 54 . .
72, 90, 108 . .
126, 144, 162 . .
180.
This approach simplifies all transactions to one-coin change. Some people might argue that this is just too many coins to keep track of, but since no one keeps track of their change anyway, it wouldn't matter. It's easier to use the new change to pay as well: Instead of $0.67 being 2 quarters, a dime, a nickel, and 2 pennies, it can be paid in one coin. Or, you could use a 50-cent and a 17-cent piece. Or two 27s and a 13! The possibilities are endlessly easy!
Some people say that it's a problem to differentiate the 99 different coins (95 new coins) by sight. There's a simple answer to this -- each coin would have a number of sides based on its amount. A 4-cent coin is a square, an 8-cent is an octogon, and so forth. So, remember, don't give them three quarters -- just reach into your pocket, feel for the coin with 75 sides, and hand it over.
Oh, and if you can't tell a 99-sided coin from a 97-sided coin by sight, perhaps you should stick to smaller denominations.
The new two-cent coins are easy to lose, so be careful.
/syle
A Canadian quarter is worth about 18 cents. Just use those.
...In other news today, hot chicks around the world were see smiling, knowing secretly that this guy is never, ever gonna get laid.
"A terrorist is someone who has a bomb but doesn't have an air force." -William Blum
Uhhh...did anyone else have to use a calculator or pencil for this one and go, "Oh, I get it. Those idiot cashiers."?
...snicker...
Any sufficiently well-organized Government is indistinguishable from bullshit.
A few years back, my dad was paying for something, and paid an uneven amount in order to get even change. The clerk looked at the money, sort of shrugged, and punched it in and started counting out the change. The catch is---my dad misheard the amount. So when the clerk started counting out a bunch of pennies and nickels, my dad was like, "wait, what?" Had the clerk had *any idea* why my dad had given an uneven amount, she would have realised that he'd misheard the price. But she just punched it in and started counting it out....
A few years after that, my sister (in 5th grade at the time) had a test with a miscalculated grade, and when my mom went in for a parent-teacher conference, she brought it up. In particular, she said she'd added up the number correct and divided by the total number of questions, and got a different percentage... the teacher looked down her nose at my mom and said, "that's *not* how it's calculated." How was it calculated? Well, you have these cardboard discs that you turn according to the total number of questions, and then you read the grade out of the little window corresponding to the number right.... This woman had only the vaguest notion that this grade was a percentage correct, and *no idea at all* that---as a percentage---it could also be calculated by dividing the numbers out. None.
``This, too, shall pass.'' ---Eastern proverb
Hey, I can beat this guy at this math thing. According to my calculations there are much more efficient combinations. For example, if you use the coins 1, 2, 4, 8, 16, 32, 64 it will take approximately 3.19 coins per transaction (this is simple binary arithmetic). That's way better than his system which takes 3.89 coins per transaction. The only problem is that the geeks will do just fine with these denominations but just try and ask the average waitress to make change using those coins. Go ahead and ask, I'm sure it will work out just fine! :)
You know, if we mint 1 coin for every amount of change (like a 57 cent coin, a 58 cent one, etc.) then it will only take 1 coin per transaction. Of course then we have to worry about having 99 different coins, making them distinguishable from each other, etc.
The current United States system of currency works just fine. Denominations of 1, 5, 10, 25 are easy enough to calculate and efficient enough for all intensive purposes. Sure this proposed new system may be 17% "more efficient" for a computer but real people need to use the system also.
Some things are best off just left alone...
Sapere aude!
Pennies are worthless?!?!?
Meet my penny-filled sock, my friend! And the sock is stinky, too!
(Gimme a break, it's noon on Friday and I'm bored outta my mind...)-
Vote monkeys into Congress. They are cheaper and more trustworthy.
<voice style="school house rock">
18...36...54...72...90....108
STOP
Multiply by 18 is like multiplying by 20 but subtracting multiples of 2. So 18*3 is really like 20*3 - 2*3. That's just 60 - 6, or 54! Let's do it again!
18...36...54...72...90...108...126...144...162.. .180!
Ready or not, here I come!
</voice>
no, I didn't use a calculator. I sure hope the math is right.
Forget $1 coins, I want a $1.0753875 coin so I can buy things that cost 99 cents.
It's just sometimes people like to do this to be helpful or just to be annoying/arrogant (really anticipating the look of panic in the cashiers eyes).
;)
I don't do it for any of those reasons. I mostly do it because I'm lazy and don't want to carry around 5 pounds worth of pennies. Oh, yeah, I also want the only jangling sound when I walk to be from my big brass ones.
Sure I'm paranoid, but am I paranoid enough?
I prefer the following : make pennies worth $1.
This would:
-eliminate the penny,
-give us a distinguishable dollar coin,
-and stimulate the economy
Pennies are visibly and tactilly different from our other coins; can be used in vending machines; are easy to carry around. Plus, Lincoln was a great guy, what with freeing the slaves and all (better than that indian-killer Jackson that's on the $20, at least) and this lets us honor him once again.
Income would be redistributed somewhat randomly to people with big jars of pennies. The ultra-rich (you know, the ones getting the big tax cuts) probably have no more than a handfull of pennies. Some people would chose to hoard the new dollars; while others would spend them with abandon. And wouldn't you like to pay your taxes by sending in several rolls of pennies?
Just for laughs, I'd make "wheat cents" worth $100.
I just failed to find any of my one sided pennies....Curse you third dimension!
>>For example, with 12 ounces in a pound
... it must have gone to Jenny Craig or was "Sweatin to the Oldies".
When did a pound lose 4 ounces? I know
I don't think those Sacagaweas "ones" are really brass - they just look it.
Sorry. Couldn't resist.
Any sufficiently well-organized Government is indistinguishable from bullshit.
In Canada they have the Loony and Toony (denziens of the maple leaf state, please correct my spelling). These are $1.00CA and $2.00CA coins respectivly.
A friend and I were in CA on business and were totally unable to figure out the stripper tipping protocol. We had a few USD which the ladies were happy to accept. But then we were down to "hard" CA currency.
"Maybe you throw them?" I asked. Of course we didn't want to risk chipping a tooth.
One of the ladies drifted over after a while and started talking. She was from the US and I asked her how it was done. She took a Loony from me and walked up to the stage, put it between her teeth and lay down on her back on stage. The performer at the time crawled up over her, mouth over mons, and crawled backwards and removed the coin with her breasts. Very Hot!
She then gestured me over, obvously expecting me to do the same thing! Having spent some time in US strip clubs, this level of contact is strictly Verboten! Enough to get you ejected into the -30 CA winter air. My friend wasn't so shy and walked up and got the ride of his life!
Canada may be cold in the winter but the ladies can be vary warm!
=Shreak