Basic statistical distributions such as Gaussian, Student, Snedecor-Fisher and chi-square are considered. Their properties are studied in order to construct effective calculating schemes for them. There are obtained exact formulae in which the functions are presented in terms of elementary functions. In sections 2, 3 of the proposed presentation this hypothesis is completely verified. In addition for the calculation of Student, chi-square and Snedecor-Fisher distributions the efficient algorithms are worked out as a consequence of the obtained results.