  The observed evidence for the existence of strange stars and the concomitant
observed masses and radii are used to derive an interpolation formula for the
mass as a function of the radial coordinate. The resulting general mass
function becomes an effective model for a strange star. The analysis is based
on the MIT bag model and yields the energy density, as well as the radial and
transverse pressures. Using the interpolation function for the mass, it is
shown that a mass-radius relation due to Buchdahl is satisfied in our model. We
find the surface redshift ($Z$) corresponding to the compactness of the stars.
Finally, from our results, we predict some characteristics of a strange star of
radius 9.9 km.
