top of page
  • Writer's pictureBill Holmes

Bagging Groceries Taught Me Everything I Needed to Know About Being an Executive Part 3

Funny meme about math and success at work

“If people do not believe that mathematics is simple, it is only because they do not realize how complicated life is.” John von Neumann

“Mathematics expresses values that reflect the cosmos, including orderliness, balance, harmony, logic, and abstract beauty.” Deepak Chopra

Lesson 3: Master basic math skills and be able to do simple equations in your head quickly! It is surprising how many times that gives you an edge.

My first “real” job was at Piggly Wiggly Southern®, a grocery store chain that was primarily based in Georgia in the early 80’s. This is the third in a series of posts describing the Executive Leadership lessons I learned in that first job.

Several months had passed and I had reached that stage of employment where the job was second nature and management trusted me to do the work without much supervision. Home to school, school to work, then work to home to study. My parents had adjusted the household schedule to sync it with mine. Every night when I got home there was a plate of whatever mom had fixed for dinner waiting for me on the stove.

One particularly slow evening I was doing busy work around the front end of the store. Even on the slowest of nights there were still things to do. The manager on duty asked me if I was interested in training on the cash register. Looking back, I must admit that I was a little intimidated by the notion of running the cash register, but I said yes.

Those weren’t the registers you are used to seeing in the stores now! This was back when every product on the shelf had a price tag on it. No computers! That meant that the process of checking out was dramatically different than you are used to seeing today. These were mechanical cash registers that were really nothing more than adding machines. The price had to be typed in and then physically “rung up”.

The physical process was to use your left hand to grab the items and while your right hand stayed on the cash register. Over time and through muscle memory your right hand “learned” where the various buttons were, and you could very quickly ring in items without looking at the cash register at all. The items had physical price tags that had been placed there by the stock crew using label guns as they stocked the store. While most items had UPC codes, Piggly Wiggly hadn’t adopted that technology yet so it was all done by hand.

To be good at the job, you needed to be very good at basic math and had to have a good short term memory. To encourage volume purchases, many products were priced in multiples such as 3, 4 or 5 for various dollar amounts. If you noticed that there were 3 of something, you could ring up the total. Often you came across these one at a time, so you had to figure out that 3 for $1 made the first two items 33 cents and the third 34 cents. If the items were larger, they could be priced 3 for $5 which made the math a little slightly more difficult. I learned shortcuts to get me there quickly and memorized the more common price combinations (3 for $5 is $1.66 each with the third being $1.68).

I had to calculate sales tax. I believe it was 5% at the time, and I learned to do those calculations in my head almost instantaneously by breaking it down into a series of smaller calculations. If the sale was $127.52, first round up to $128. 5 times 1 is 5; 5 times 2 is 10; 5 times 8 is 40. Add to get $6.40 and ring it up!

I had to calculate the change to return to the customer. These were the days before you could pay with a credit or debit card, and most people paid with cash. You had to take whatever they handed you and quickly figure out what they were due back. It was always fun when someone tried to help by making the change an even amount by handing you a pile of bills and loose change! Often their math was wrong, so you and to watch for that as well.

All this had to be done instantly with a line of customers staring at you.

It is true that this is simple addition, subtraction, multiplication and division, but how many of you routinely do these calculations in your head? If asked what 17% of 80 is, do you do it in your head or reach for your phone? If you do it, how many of your colleagues do? Next time you are at dinner ask whomever you are out with to calculate a 15% tip and see what happens. I still do these calculations mentally because that is how my mind got “wired” after running a cash register for a few years.

You may be reading this and thinking: “So what? How does that help you today?”

It helps a lot.

First example. There are many times when I am in a committee meeting of one type or another and the topic turns to funding. I find that if the information is presented in percentages, converting it to dollars (for a United States based project) does two things: 1) it changes the tone of the discussion 2) it makes it appear as if you are well prepared. For example, you may have just been told that the project needs 32% more funding next year than the current year base of $22M. If you can immediately ask the question “Are you asking for $7M more in funding?”, it appears as if you had the information all along when all you did was quick math.

Second example. Information is often presented as individual line items, or they are grouped in a way that isn’t advantageous to your position. It is often helpful to quickly regroup them in a way that emphasizes the point you want to make, and if the data is presented in whole numbers a quick conversion to percentages provides an added advantage. I was in a meeting a while back and we were looking at a series of projects under consideration. I wanted funding for infrastructure, and I noticed that the projects weren’t grouped that way. I quickly totaled the projects that were for infrastructure and realized that they were less than 10% of the total. I made that point and the discussion changed completely.

Third example. Any time there is an opportunity to make a public display of quick math. I often find myself traveling with colleagues and we will have dinner together. Some establishments won’t split the check, so being able to instantly determine the tip and quickly calculate everyone’s portion is something that is impressive. Doing so while people are reaching for their phones to do the math is doubly so! Business dinners still count as work, and people will remember those seemingly innocuous moments like that.

The ability to quickly to do simple calculations, especially moving back and forth between fractions, percentages and whole numbers is something that many people can’t do. If you can, it gives you a significant advantage both at work and in day to day activities.

Now was the service today worthy of a 15% or 20% tip?


As I shared in an earlier article, Piggly Wiggly Southern expanded rapidly, then quickly contracted as a result of what I believe were a series of poor management decisions. They were slow to embrace new technology and ignored the input of their local managers. An example of that was the use of UPC codes. I recall that one of the district managers refused to allow the roll-out of scanning technology because he believed that “no customer would trust the computer to get the price right”. That one decision cost the company millions in labor dollars as employees had to place labels on every product and then scrape it off when the price changed. You also lose the ability to systemically track inventory, analyze trends in purchases, etc. What a shame.


bottom of page