If an event has a 4% chance of occurring everyday. What is the chance of said event occurring after 30 days?

Hi askscience, long time lurker. Anyways, I've been in a little math discussion with a friend about this tonight. If something has a 4% chance of occurring everyday, what is the chance the event happens after 30 days? Our gut instinct was 120% but that doesn't really make sense to me. I have an M.S. in a non-technical degree but I've had a few graduate level statistics courses (mostly ANOVA/ANCOVA/MANOVA/Regression stuff) so I'm embarrassed I can't figure this out on my own....

Thanks!