Math Problem

Where did the money go?

There were three friends having dinner together, when the waiter brought their bill, which was $30. Each paid $10.
After collecting the money the waiter realized that t he bill should have been $26 insted, dua to a special discount.
Unsure on how to divide $4 equally among three people, he put $1 in his pocket ang gave each person $1. This means that each person paid $9 for their dinner.
It happens that 9 x 3 + 1 = 28. What happened to the other $2?

I love this question because people try to answer it. The fact of the matter is, you can't. You can't go backwards in math. The simple answer is, "we don't know" another example is: If I drive 40 mph for the first mile of my trip and 60  mph for the second mile of my trip, how fast must I go on the third mile to average 50 mph? It's impossible to know.

Also, let's try it this way. 2. Where did the 2 come from? was it 4-2 was it f'(x) = 2x ? same thing

The problem arises in the problem when we assume that each person "paid 9 dollars"