Okay, before I get into this explanation, I need to give my reasoning, I guess.
I might get fussed at for this, as some high-ups might think this is a common sense thing, but guess what guys? It isn't!
I can't count the number of times I've been in the grocery store and tried to do this with the clerk, only to have them look at me so flabbergasted that they don't even think to put what I gave them into the damned register and let it tell them what to give me back!
So let's face it, given the youth and their tendency for laziness, it isn't a common sense thing people, I'm sorry.
So now, on to spending small change! Now, figure this: before we had debit cards, and credit cards, and even checks (but after the end of the bartering system, of course, although technically the system of bartering is still in place; don't we trade money for what we want? And how about the market? But I digress), there was really only one way to pay for what you wanted: You whip out your handy-dandy billfold, or whatever the heck you keep your money in, and you use bills and coins.
Well, at some point, some smart people gradually figured out how to reduce the amount of small change they get back from transactions. Before we end up living in a cashless society, thanks in part to wonderful plastic, it would do well for some to learn this little secret.
Let's say you're in a convenience store and you get a bottled soda and a candy bar. Well, at the store I work at, this would generally come up to $2.88 after tax (Mom says when she was a little girl, she could get a fountain coke, a candy bar, and a comic book for a quarter, all I could say was "Wow").
Well, so you go digging for money. The two isn't a problem, just use two ones, but you discover that you don't have eighty-eight cents! What now? Well, you do have three pennies and a nickel, so pull out another dollar bill and give the clerk $3.08. Now why and how does this work?
Eight cents is comprised fundamentally of a nickle and three pennies, so by giving the clerk the penny part, you can avoid getting any pennies back. The resulting change from this would be twenty cents. Two shiny dimes. Pretty nice, right?
Simple but applicable question: What happens if you just give him $2.08? It isn't enough! You'd still owe him another eighty cents. That's where the other dollar bill comes in, and you get your twenty cents back out of that.
Let's give another example. You're in the grocery store, and the cashier just got done ringing up your purchase. Your total is $107.49. Yikes! I know what you're thinking: "Alright, smarty pants! Change your way outta this one why don't you?"
Alright, I will. While most people would just give the cashier a hundred dollar bill and a ten dollar bill and take the change ($2.51), I like to keep people on their toes. So I'll give the old chum $112.54.
There you go again! "One twelve fifty-four? What the hell is wrong with you, man?"
Let's take the small part first. This is simple math, 54 - 49 = 5. One nickle is the only coin I'll be getting back, and that's a good feeling if you don't like a ton of jingle in your pocket. Let me iterate this carefully for you. Any time the last digit of your balance is 9, giving up four pennies will stop you from getting any in return.
"Yeah, but why'd you give him 112 for 107?"
Well, that's the more crucial part of the deal. Again, do the math: 112-107 = 5. Ignore the 100 part, Big Ben will take care of that. Seven dollars is principally a five and two ones, right? Well, giving him the two ones will even things out and allow the cashier to half the ten, giving me a good ol fiver back.
See, using this technique, I manage to get back a single bill, and a single coin. Pretty nifty, eh?
Now, for something that really annoys me as a gas station clerk. If you pump gas, and you go over a penny, but you get other stuff too, unless the last digit of your new total is somehow still a 1, that single penny won't help you, put it back.
Example: Suzy pumps $10.01 gas, then comes in and gets Marlboro cigarettes. Her new total is now $13.99. Unless she has three more pennies to go along with the one, if she gives me $20.01 her change will be $6.02. Yuck, not only do I have to give her the original penny back, but now it has a buddy!
Now, am I saying you have to do this? Hell no! It's a free country, do what you want. As long as you aren't endangering innocent people (as if there is such a thing any more), we'll be ok. But it does help if you don't like toting around a bunch of pennies and ones. Obviously if you have the complete change, give that, and you can get whole dollars back, but if you ever look at your handful of change, and see part of the amount, now you know how to help yourself.
In closing, let me say that, for me, coins are a convenient way to save. I put all my change in a coin bank at home, except for four measly pennies. Why? Because those four pennies will be the most I'll possibly need to get shiny silver back instead of rusty copper. Once the ol coin bank gets full, I take it to the bank and use its handy coin organizer to deposit all that change straight into my savings.
So you see, it all really is a matter of personal preference. I just figured I'd put this node on here to help out some people who might genuinely want to learn how to stop themselves from always getting back so many ones and pennies.