If numbers can be rounded to make math easier this is most often a good idea. Differential Calculus cuts something into small pieces to find how it changes. This will show us how we compute definite integrals without using the often very unpleasant definition.
This means you must learn how to do complex calculations using pencil and paper or better yet in your head.
And thanks to the Internet its easier than ever to follow in their footsteps or just study for that. Rule for cross multiplication of an even number of digits. I will be falling at exactly 10 ms. This free video math lesson will show you how its done.
