I had sex on days cd9,10,and 12 of my 24 day cycle what are the chances i conceived?

It sounds like you are trying to conceive, as I assume all of those days were unprotected sex?! This is a very exciting, and emotionally exhausting, time for you!

Your chances of conceiving, similar to every women without known fertility issues, is 20% with every cycle. The more times you have unprotected sex, the better your chances (within the 20% range).

Hang in there!