# Large numbers are hard to understand

Lots of people have a blind spot for numbers. Especially large numbers, like a million or a billion. Lots of people think that numbers like a million, a billion, and a trillion are evenly spaced on the number line, like 1, 2, and 3 are. But the amount of space between a million and a billion dwarfs the distance from 1 to a million. A billion is a thousand millions.

Here’s another way to look at it. It takes about 12 days for 1,000,000 seconds to elapse. But it takes about 32 years for 1,000,000,000 seconds to elapse. They are so far apart. But most people just stop thinking about what these numbers really mean, and kind of lump a million and a billion together. Kind of like “they’re big numbers, and a billion is bigger than a million”. Well, yes, that’s true. But it loses how much bigger, and it’s a lot.

# Save lives for under a buck

A previous student of mine showed me this video, which actually ties in with something I had just found out about a few weeks previously. By combining a cheap, paper microscope that cost about \$0.50 to make, and a child’s spinning toy, it is possible to diagnose malaria, which kills millions each year. The microscope is called the Foldscope. It’s printed on a heavy piece of die-cut paper, and then gets cut out and folded into a surprisingly powerful microscope, able to see blood cells. You can preorder these yourself (I have!). The other piece, the spinning toy, replaces expensive centrifuges to separate the blood into components. Coupled together (along with a doctor) you can do the lab work for diagnosing malaria for under \$1.