Mathematics is formulas and theorems, concepts and numbers. In today's world mathematics is also in computers. That is where the rubber hits the road.
Putting numbers inside of computers isn't as easy as it sounds. Putting decimal numbers into computers is fraught with problems.
Should you ever find yourself programming computers in a way where the computers are manipulating numbers for you please sit down and read What Every Computer Scientist Should Know About Floating-Point Arithmetic.
It's not as easy or as simple as you think. Let David Goldberg tell you about many of the pitfalls and problems in getting computers to represent numbers.