How high can you count on your fingers? (Spoiler: much higher than 10) - James Tanton

Toggle fullscreen Fullscreen button

Sharing buttons:

How high can you count on your fingers?

It seems like a question with an obvious answer.

After all, most of us have ten fingers,

or to be more precise,

eight fingers and two thumbs.

This gives us a total of ten digits on our two hands,

which we use to count to ten.

It's no coincidence that the ten symbols we use in our modern numbering system

are called digits as well.

But that's not the only way to count.

In some places, it's customary to go up to twelve on just one hand.


Well, each finger is divided into three sections,

and we have a natural pointer to indicate each one, the thumb.

That gives us an easy to way to count to twelve on one hand.

And if we want to count higher,

we can use the digits on our other hand to keep track of each time we get to twelve,

up to five groups of twelve, or 60.

Better yet, let's use the sections on the second hand

to count twelve groups of twelve, up to 144.

That's a pretty big improvement,