help with ratios? please?

[etheesdad]

Hi Ive read the faq and have been looking around and can't seem to get a grasp of how the ratio system works.

Our stupid ISP counts uploads as well as downloads in our measly 2gb limit, so I am trying to work out how to download with minimal uploads. And if you're wondering, NO I don't just want to leech, I understand that the community works by sharing and Im happy to participate in this.

My question is, is there a simple formula that a non maths-head like me can understand so that I can download a large file without uploading a huge amount of data also?

Thanks to anyone who offers assistance with this. Respectfully, please don't reply if its just a flame or a lecture about sharing. As I said, Im happy to share I just don't want to blow my months limit on one or two downloads.

Thankyou