Here's a method that works really well whenever you have to do math fast, on your feet, in public.
$39.99 = $40.00 (What's a penny, eh? I'M 40, and if there's supposed to be some kind of Freudian psychology to this, it's NEVER worked on me. EVER. Not at the mall mom dragged me to four times a week in the '70s, and n...more