How Many Coffees Can I Buy?

Imagine this: I’m a coffee lover with only 10 dollars to spend. But here’s the twist—each cup of coffee costs a random price between 0 and 10 dollars. So, on average, how many cups can I actually buy?

If you’re curious about the answer, check out the video!

For a theoretical justification (a little probability theory is needed), you can watch the video (in Chinese) below: