You are drawing a map of your school and want to make sure all the measurements are accurate. You decide to use a scale of 1 cm = 3 feet. In your drawing, the main hallway ends up being 12 cm long.

The drawing is a little too big so you decide to change the scale to 1 cm = 4 feet.

Keeping the length in feet the same, how many centimeters long should the main hallway be in your new drawing?