One of my dad’s favorite possessions was his slide rule.  It is, apparently, quite the deluxe model, as slide rules go.  Furthermore, he obtained this luxury at a great discount from the college bookstore because personal calculators had just become affordable and no one wanted slide rules anymore.  Daddy was a math geek who tried very hard to make me into a math geek.  Unfortunately for him, while I had no trouble understanding math, in the words of one of my teachers I “just didn’t like it.”  Nonetheless, we found math geek points of contact.  I am reader and occasionally writer of fantasy and have been since middle school, when a favorite father-daughter activity was applying geometry to design the MOST DEFENSIBLE CASTLE EVER.  But at the end of the day, I was more interested in the people in the castle than in its construction or defense.  Sorry, Dad.

I remember getting a fast food meal with Daddy.  I believe it was at a Wendy’s, and it was probably on a Wednesday, either before or after Wednesday evening church.  The total for the order came to a dollar amount (let’s say eleven), plus change (we’ll go with thirty one cents).  Daddy gave the cashier a twenty and pulled a nickel and a penny from his pocket.  The cashier must have hit the twenty dollar button on her register while Dad was retrieving the coins, because she looked at the change he put in her hand with abject horror.  Dad explained that by adding the six cents to the amount tendered, she only needed to give him back eight dollars and seventy-five cents (that is, all bills and quarters) rather than eight dollars and sixty nine cents (which is an obnoxious amount of change to count out, much less carry in one’s pocket).  I think the cashier’s response of “Say what?”  With a sigh, Dad sketched out the math for her on the back of a receipt and – I think – still without being totally convinced, she gave him the eight seventy-five.

Back in the car, square cheeseburgers in hand, Daddy fell into an extended rant on how sad it was that cashiers didn’t know how to count change.  I offered something about how the register does figure it for them.  (Remember that I’m probably thirteen or so in this story and, therefore, at the peak of teenage insufferable-ness.)  This is rejected as a bad excuse because the computer could break, or a customer could hand or coins, or the martians arrive with heat rays, or some other scenario wherein the brain needs to understand how to count.   Daddy followed this up with a detailed explanation of the correct method of counting change backward from the total charge to the amount tendered.

This past week, my bossfolks were out of the country, and I was left to run the store with the other employees with all the de facto authority accorded the senior staff person.  By hitting a button wrong, the bossman managed to lock me out of the entire POS system.  I couldn’t even clock in much less assign myself a cash drawer.  The other morning cashier could clock in, but the computer was programmed to only allow her to run credit cards.  She couldn’t accept cash.  The third cashier could not be clocked in or assigned a drawer until his scheduled arrival time.  By the time I figured out how badly my hands were tied, I was ready for the Martians to show up with their heat rays.

After three days of counting change back manually and keeping hand records of cash transactions all I can say, “Daddy, you were right.”