The Riddle Thread

[Tisthammerw]

Here's a problem (it's easy for me to solve, but maybe that's because I minored in math). I borrowed this one from MindTrap.

If you were given a can of cola that was 97% caffeine-free (relative to a normal can of cola), how many cans of cola would you have to drink to consume the same amount of caffeine in a regular cola?

Note: there's a clever trick you can use here to make the calculation easy. (And you don’t need to have minored in math to figure it out.)