This paper explains the use of unequal probability sampling in finite populations Cochran (1977). Comparison among the well known selection procedures have been carried out. Variances of the estimated population total from all possible samples and exact variances have been calculated. Numerically it has been shown that for population where either the mean per element is proportional to Y1/ P, or rises as size increases with high correlation, the unequal probability sampling method is better than equal probability method.