23 people. In a room of just 23 people there’s a 50-50 chance of at least two people having the same birthday. In a room of 75 there’s a 99.9% chance of at least two people matching.| betterexplained.com
Our world is numbered. Books have ISBNs and products have barcodes. Cars have VINs, even people have social security numbers.| betterexplained.com
Ratios summarize a scenario with a number, such as “income per day”. Unfortunately, this hides the explanation for how the result came about.| betterexplained.com
A sense of scale helps us better understand the world, and convey ideas more effectively. What’s more impressive?| betterexplained.com
Here’s a collection of time-saving math shortcuts, great for back-of-the-envelope estimates.| betterexplained.com