Tips for calculating the average age of death in Questions 1 and 3.
You are using the median as representative of the age range. To calculate the median, subtract the lesser number of the range from the greater number, and divide the result by two. Then add this result to the lesser number of the range. For example, the median of age range 15-19 is 17, and the median of age range 40-49 is 44.5.
To calculate the average age of death, you must calculate a weighted average (illustrated below). To do so, multiply each individual median by the appropriate number of deaths (e.g.. 2 x 386 = 772, 7 x 98 = 686, etc.). Add the total results together (16244.5) and divide by the total number of deaths (955). Your answer for the average age of death in the Old Kingdom is 17.