Thus far, we've only dealt with methods that only accept a single object as an argument or parameter. We'll expand this and talk about the ways in which methods can accept more than one parameter.
Let's take this slow and begin with two parameters.
So, adding a second parameter is really simple - just add the new parameter separated from the original by a comma.
Parameters can have default values too. Let's say we usually add three numbers, but occasionally just add two. We can default the last parameter in the previous example to 0 if nothing is passed to it.
Older versions of Ruby - 1.8.x and older - required you to set default values for parameters starting with the last parameter in list and moving backward toward the first. The current version of Ruby (1.9.x) no longer has this limitation, but it's worth mentioning since Ruby 1.8.7 is still in use.
Ok, your turn. I shall simply ask that you make the tests pass for the exercise below.