What is Math LLC

Did you wait all weekend in anticipation of what Day 2 would bring?! It’s spring, and our goose pond is growing algae like crazy. Help us figure out when it will be half full (or half empty if you’re that kind of person).
Our unofficial hint for this one is to not think too hard. As always, DM us if you need a hint and to check your solution! Solutions for the week will be posted in our stories on Friday. Happy algae counting!

Day 1 is HERE! That's right, it was not an April Fool's Joke. Get your PEMDAS on! Don't remember what that is? Good luck.
DM us for the hint of the day & to check your answer! Read comments at your own risk.