A group of amateur engineers wants to find the center of mass of a person using a simple experiment. They set up a 3-meter-long, 6 kg wooden plank horizontally, placing one end on a scale and the other end on a support. A 55 kg participant lays down on the plank, positioning their feet above the support. The engineers read the scale and observe that it measures a mass of 22 kg. Determine the distance from the participant's feet to their center of mass.