Estimated Mean Sum of Midpoint FrequencySum of Frequency. Because all values are used in the calculation of the mean an outlier can have a dramatic effect on the mean by pulling the mean away from the majority of the values. How To Find Mean Median And Mode From Frequency Table The Frequency Distribution Table in statistics provides the information on the number of occurrences frequency of different values distributed within a given time or over a given interval in a list table or graphical representation. . How to find the mean of frequency distribution. Page A-2 of 4 Rainfall Intensity-Duration-Frequency Curves Table A-1 Example IDF calculations for 5 to 20 minutes 5 to 20 minutes. The x with the bar on top says the mean of x So now we are ready to do our example above but with correct notation. The following frequency table shows the total number of pets owned by 20 different families in a certain neighborhood. - Assume...