A “20% off” sign looks simple until a store stacks it with a coupon code, a loyalty discount. A clearance markdown all on the same item. Shoppers often assume the discounts just add together —…
A “20% off, plus 8% sales tax” receipt looks simple until you try to reconstruct the math yourself, and the order in which you apply the discount and the tax changes the final total more…
Every sale sign says “40% off” or “extra 20% off,” but if you’ve ever stood in a checkout line doing mental math and gotten a different number than the register, you already know that learning…
