1.
Centre of mass (C.M.) of three particles of masses 1 kg1\,\text{kg}, 2 kg2\,\text{kg} and 3 kg3\,\text{kg} lies at the point (1,2,3)(1, 2, 3) and C.M. of another system of particles of 3 kg3\,\text{kg} and 2 kg2\,\text{kg} lies at the point (−1,3,−2)(-1, 3, -2). Where should we put a particle of mass 5 kg5\,\text{kg} so that the C.M. of entire system lies at the C.M. of the first system?