# Blog

## Two billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine…

2014-12-22 18:07:00 GMT

*We celebrated with cake pops in the shape of a big 3, making the day all the sweeter…*

Today’s an exciting day for us – together we’ve just hit the 3 billionth problem answered on Khan Academy!

We asked Sal what he thought of this, and he said, “Personally, I don’t know what all the fuss is about. I’m waiting for us to hit 3 141 592 653 problems solved before I get really excited.” Can you help us get to pi billion?!

The rate at which everyone is learning on Khan Academy is astounding: it took less than a year to grow from 2 billion to 3 billion problems answered! Way to go!

And just how big is 3 billion, exactly? We did some digging …

- If you had a measuring tape that was 3 billion inches long, it would wrap around the world twice.
- If you traveled a mile for every problem that’s been answered, you’d almost be at Pluto.
- If you went back in time 3 billion minutes, it’d be the 37th century B.C.E., a thousand years before the Egyptian pyramids were built.

Whoa, that’s a lot of learning.

So… how quickly can we get to 4 billion? Let’s go!