The Mystery of the Vanishing Nickel (In other words, a nickel for your thoughts.)

The American Prowler ^ | 1/7/2005 | Lawrence Henry

[Miss Marple]

Oh, I see what you mean. Sorry...I haven't had enough coffee yet.

By the way, I noticed those lanes for the transponder, but I didn't realize that was how they tracked you through those lanes.

I think I contributed about six dollars to the Illinois tollway on this trip. At least I remembered to get a lot of change before I left, so I didn't have to go through the manned booths.

[Boot Hill]

8	“I suspect that clerks often substitute dimes for quarters, probably because they notice their change drawers running short of quarters”

Maybe, but it also might have to do with which denomination coins are the most plentiful in the drawer.

1. Here are the number of coins needed to make all change from 1¢ to 99¢...
   

   	quarter	dime	nickel	penny	total
   number of coins	150	80	40	200	470
   percentage	31.9%	17.0%	8.5%	42.6%	100.0%

2. While that table says we need 8.5% of our coins to be nickels, that doesn't mean we need 8.5% of our volume to be nickels. This is because the different denominations take up different volumes per coin.
   

   	quarter	dime	nickel	penny
   $ per cu. in.	$4.66	$4.47	$1.06	$0.34
   coins per cu. in.	18.6	44.7	21.2	34

3. Combining tables 1 and 2 (and doing a little calculating) we get...
   

   	quarter	dime	nickel	penny
   number of coins	150	80	40	200
   coins per cu. in.	18.6	44.7	21.2	34
   required cu. in.	8.1	1.8	1.9	5.9
   relative drawer width	4.3	.9	1.00	3.1

It's after 2am so don't expect me to jump in the car and drive the 15 miles to the Safeway store to measure their cash drawers, but as you can see from table 3, any relative drawer widths other that shown in the last row will result in an unnatural preference for the more plentiful coin. That preference could explain the phenomenon that author Lawrence Henry noted in the article.

--Boot Hill

[sharktrager]

Nickles are the least used coin (besides half-dollars and dollars) because it is the only coin you should in theory never get more than 1 of in change. 2 nickles are of course a dime.

[numberonepal]

They can't add, multiply, divide or subtract.

When I was growing up my Dad owned a small C-store. I learned how to count back change without the help of the register by counting "up". You rarely see this any more except in older folks. However, the other day I ran across a kid (16-18) that actually counted back my change without the use of the register. I was shocked and amazed to see this.

[garyhope]

Mr. Boot Hill, You seem like a real interesting guy, but perhaps you need more to do in your life, however you're probably fun to talk to.

You must be an insomniac like me, pacing the floor at 2 AM thinking strange thoughts.

I think measuring the cash drawers at Safeway at 2 AM might have been a little much, but thanks for the thought.