Sales Commission Formula

Hey guys. I hope this is the right section. I work in sales and I have a breakdown of my commission plan. If I sell so many I am considered in a 10,20,30,....100,110,120, etc. percent to goal. The amount paid for each item goes up for different percentage to goal that I get. What I would like to do is create a formula that if I plug in I have so many sells of whatever products then it will tell me my estimated commission. Also if possible the opposite. Let's say I need to make $3000 on my next check how many services I would have to sell.


I hope I explained this well enough but please leg me know if I forgot something.

Thanks,
Dustin