New Delhi, April 27 -- Picture this, a flashy "limited-time" offer, a crowd rushing in, and almost nobody stopping to do the math. That's the power-and peril-of missing basic numeracy.

In a world flooded with flashy deals and fine print, basic numeracy-the ability to understand and work with numbers-is more important than ever. Yet time and again, people fall for offers that don't add up, misunderstand financial terms, or overlook critical details that could save (or cost) them real money.

Two stories-one from fast-food history and another from my experience in the world of microfinance-illustrate the profound consequences of innumeracy.

Also read: Investing in mutual funds does not start and end with just SIPs

The burger blunder

In ...