  The ATLAS and CMS experiments at the Large Hadron Collider (LHC) may discover
the squarks (\tilde{q}) and gluino (\tilde{g}) of the minimal supersymmetric
standard model (MSSM) in the early stage of the experiments if their masses are
lighter than 1.5 TeV. In this paper we propose the sub-system m_{T2} variable,
which is sensitive to the gluino mass when m_{\tilde{q}}>m_{\tilde{g}}. Using
it with the inclusive m_{T2} distribution proposed earlier, \tilde{q} and
\tilde{g} masses can be determined simultaneously in the early stage of the
experiments. Results of Monte Carlo simulations at sample MSSM model points are
presented both for signal and background.
