I'm a horrible mathematician ... horrible. So when I see these words in a pattern I have two options. I can either wing it and then resent my project for being "wrong" or I can go to this website and have the calculator do it for me. There's also a calculator for increasing evenly on the same site. When I found the site I thought it was the greatest thing since sliced bread ... and well I still think it is :)
Do you know of any useful tools like this that you would like to share with me?