In one dimension, an inertial ball of mass 1 kg has a speed of 1.50 m/s to the right and another inertial ball of mass 3 kg has a speed of 2.00 m/s to the left. After 10 seconds, they meet in a head-on inelastic collision. The collision is not perfectly inelastic, meaning that the balls lose kinetic energy, but do not stick together after the collision. Find the velocity of the center of mass after the collision in m/s (- for left moving and + for right moving)