  We present a model of an inhomogeneous universe that leads to accelerated
expansion after taking spatial averaging. The model universe is the
Tolman-Bondi solution of the Einstein equation and contains both a region with
positive spatial curvature and a region with negative spatial curvature. We
find that after the region with positive spatial curvature begins to
re-collapse, the deceleration parameter of the spatially averaged universe
becomes negative and the averaged universe starts accelerated expansion. We
also discuss the generality of the condition for accelerated expansion of the
spatially averaged universe.
