Abstract: Statistically the median and mean deviataion of the data collected from experiments and observations are usually used as the characteristics values of partial distribution. The product of frequency and absolute values of deviate (fi|xi|) should be calculated for calcuatiug the mean deviate. In case of many grouping data, the calculator program of Casio fx-3600p (fx-180p) can make the calculation fast and accurate where the minimum Xi is stored independently , thefi|xi| is accumulated and the stored products is calculated using the language for selecting positive and negative values.