Assignment

When Mathematica computes an answer, it prints it out on the screen and then goes on
to the next question. Often we would like to save an answer and use it later.
Mathematica provides {\it assignment} as a way of doing this.

For example, suppose that we'd like to average two numbers and save the result:

average = (12 + 83) / 2;

Now the symbol average stands for the average of those two numbers. We
can use it later just like any other number. For example:

average*5