  We present here a phenomenological cosmological model under perfect fluid
distribution with a stiff equation of state $p=\rho$. The erstwhile
cosmological constant is assumed to be a time dependent variable, i.e.,
$\Lambda = \Lambda(t)$ in our study. It has been shown that the estimates of
different cosmological parameters from this model are in good agreement with
the experimental results, especially 13.79 Gyr as the age of the universe is
quite satisfactory. The behavior and relation of $\Lambda$-stiff fluid model
with dust, viscous fluid and variable $G$ have also been investigated in
detail.
