In multi-stage rockets, the stage mass fraction is defined as
Show Hint
For a rocket stage,
\[
\boxed{
\text{Mass Fraction}
=
\frac{m_p}{m_{\text{stage}}},
}
\]
where
\[
m_{\text{stage}}
=
m_p+m_s,
\]
\(m_p\) is propellant mass and \(m_s\) is structural mass.