In theory, both will hit the ground (assuming it is level) at the same time. I remember 40+ years ago a physics experiment called the hunter and the monkey. The premise was a hunter aimed at a monkey hanging from the branch of a tree. Just as the hunter fired, the monkey let go. Would he hit the monkey? The practical session sadly didn't involve either a monkey or a rifle - just two ball bearings. One was held by a solenoid about 6 feet from the floor. Another was rolled along a horizontal ramp at the same height. A photo-switch at the end of the ramp de-energised the solenoid allowing both balls to drop at the same time (eventually, as sometimes the photo-switch failed, much to our amusement). Using a then state-of-the-art polaroid camera and a stroboscope in a darkened lab, it was shown that they both hit the floor simultaneously.
Ah.... happy days
Donald