  A $k$-out-of-$n$ system consisting of $n$ exchangeable components equipped
with a single cold standby component is considered. All the components
including standby are assumed to be dependent and this dependence is modeled by
a copula function.
  An exact expression for the reliability function of the considered system has
been obtained. We also compute three different mean residual life functions of
the system.
  Finally, some numerical examples are provided to illustrate the theoretical
results. Our studies subsume some of the initial studies in the literature.
