This study examines the phenomenon of vibrational resonance (VR) in a classical positiondependent mass (PDM) system characterized by three types of single-well potentials. These potentials are influenced by an amplitude-modulated (AM) signal with $\Omega\gg\omega$. Our analysis is limited to the following parametric choices: (i) $\omega_0^2$, $\beta$, $m_0$, $\lambda>0$ (type-1 single-well), (ii) $\omega_0^2>0$, $\beta <0$, $2< m_0 <3$, $1< \lambda <2$ (type-2 single-well), (iii) $\omega_0^2>0$, $\beta <0$, $0 Ключевые слова: position-dependent mass system, amplitude-modulated signal, vibrational resonance, hysteresis, chaos