The discrete distributions approximation with continuous distributions have always
been used and taken into consideration, for example, the normal distribution has been
used for related approximation probabilities to poisson or binomial distribution [1].
Karl Pearson for the first time, investigated the continuous curves to the discrete
probability functions. He suggested Pearsons’s family that included twelve members
of probability density functions. The details related to this family have been presented
in Elderton (1968) and Pollard (1977) essays [2, 3].