The velocities of three particles of masses 20g, 30g and 50g are 10→i,10→j, and 10→k respectively.
The velocity of the centre of mass of the three particles is
vcm=20×10ˆi+30×10ˆj+50×10ˆk100=200ˆi+300ˆj+500ˆk100
vcm=2ˆi+3ˆj+5ˆk.