Two bodies of mass \( 1\,\text{kg} \) and \( 3\,\text{kg} \) have position vectors \( \hat{i}+2\hat{j}+\hat{k} \) and \( -3\hat{i}-2\hat{j}+\hat{k} \) respectively. The magnitude of position vector of centre of mass of this system will be similar to the magnitude of vector:
