QTĐC:
$\rm \text{m1: 5%} \hspace{9cm} \text{10% - 8%} \\\hspace{4cm} \huge{\searrow} \hspace{2,5cm}\huge{\nearrow} \\\hspace{6,2cm}\text{8%} \\ \\\hspace{4cm} \huge{\nearrow} \hspace{2,5cm} \huge{\searrow} \\\ \text{m2: 10%} \hspace{9cm} \text{8% - 5%}$
`-> (m_1)/(m_2) = (10% - 8%)/(8% - 5%) = (2%)/(3%) = 2/3`