  Bianchi type V matter filled universe with varying lambda in general
relativity are investigated by using the law of variation for the generalized
mean Hubble parameter. This yields the constant value of deceleration parameter
and generates two types of solutions for the average scale factor one is of
power law type and other is of exponential type. The cosmological constant is
found to be a decreasing function of time, which is supported by results from
recent type Ia supernovae observations. Also it has been found that
cosmological constant affects entropy. Some physical and geometric behaviour of
the models are discussed.
