Years ago, I took Philosophy 101. I thought I was a pretty good student. One day, the prof asked if anyone had a calculator handy. I said, "Why on earth would philosophy students have calculators?" The prof replied, "Well, surely you people take other courses!" It was all pretty funny back then, but I’ve since learned to keep a calculator handy.
I do most math in my head. But, if you’re in a meeting with a prospective client, a calculator can help you work through sales deals. You can estimate costs, hours, margins — anything that involves numbers. A calculator can help you decide whether to take on a job or whether to negotiate a better deal.
If you don’t have a calculator in your briefcase, think about buying one.