So to all you bitcoin investors/miners/talkers that think you know your math I've got a math riddle for you to chew on...

The question is How do you make 100 using only four 9s you have to use all four 9s and only four 9s and you can do anything that obeys the laws of math but there can be only four 9s in the answer and no other numbers besides the sum which is 100.

What is the equation?

I really love this stuff...

By stuff I mean well stuff...