After sliding down a snow-covered hill on an inner tube, Ashley is coasting across a level snowfield at a constant velocity of +2.7 m/s. Miranda runs after her at a velocity of +4.5 m/s and hops on the inner tube. Determine how fast do the two of them slide across the snow together on the inner tube?
Ashley's mass is 71 kilogram and Miranda is 58 kilogram. Neglect the mass of the inner tube and any friction between the snow and the inner tube.