Is $22/7$ equal to the $\pi$ constant? 
Possible Duplicate:
Simple numerical methods for calculating the digits of Pi
How the letter 'pi' came in mathematics? 

When I calculate the value of $22/7$ on a calculator, I get a number that is different from the constant $\pi$.

Question: How is the $\pi$ constant calculated? 
  (The simple answer, not the Wikipedia calculus answer.)


In answer to your second question, NOVA has an interactive exhibit that uses something like Archimedes method for approximating $\pi$.  Archimedes method predates calculus, but uses many of its concepts.  
Note that "simple" and "calculus" are not disjoint concepts.   
