The blood red cups of Halloween-Jack hold green vampire bats. These bats fly into the ears of students that fall asleep in math class. They flutter around in the sleeping student's head. Students attacked by these bats will sleep through the class change. They will wake up in the middle of another class with the entire room staring at them.

Each cup of Halloween-Jack is filled with 3 bats each. It takes 4 bats to attack a sleeping student. If he released all his bats into your school, how many students could be attacked at one time?  

 

This is Halloween-Jack's entire blood red cup collection. Use it to find the answer.

Dungeon