We present a set of evolutionary computations for binaries with a B-type primary at birth .
Some liberal computations including loss of mass and angular momentum during binary evolution are added to an extensive grid of conservative calculations .
Our computations are compared statistically to the observed distributions of orbital periods and mass ratios of Algols .
Conservative Roche Lobe Over Flow ( RLOF ) reproduces the observed distribution of orbital periods decently but fails to explain the observed mass ratios in the range \in [ 0.4-1 ] .
In order to obtain a better fit the binaries have to lose a significant amount of matter , without transferring too much angular momentum .