Knowing how much can be accomplished in a given amount of time is an important element of planning. When the tasks are similar, or take around the same amount of time, it's fairly easy to determine tasks per hour. When they're more diverse, or take significantly different amounts of time to complete, the calculation process becomes more complex. Measuring productivity is an indispensable component of increasing productivity.
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Similar Tasks or Times

Use this approach to determine how many tasks can be completed in an hour when they are similar or repetitive, such as on a factory assembly line. First, record the time taken (in minutes) to complete each task on a sheet of paper.

Record the total number of tasks. Let the total number of tasks be represented by "n".

Add the task times recorded to obtain the total time (in minutes) taken to complete all the tasks.

Calculate the arithmetic mean or the average time to complete one task by dividing the total time to complete all tasks by the number of tasks completed (n). For example, if three consecutive tasks took five minutes, six minutes, and nine minutes to complete, then the average time for one task would be 6.7 minutes, or 20 minutes (which is 5 plus 6 plus 9) divided by three tasks.

Divide 60 by the arithmetic mean to obtain the total number of tasks of similar duration completed per hour. For example, 60 divided by 6.7 is nine tasks per hour.
Significantly Different Tasks or Times

Employ this more complex approach when the tasks involved vary widely  for example, determining how many different jobs a mechanic in an auto repair shop might complete in a day. First, record the time taken (in minutes) to complete each task on a sheet of paper.

Record the total number of tasks. Let the total number of tasks be represented by "n".

Calculate the geometric mean time to complete one task by finding the nth root of the product of all task times. For example, if three tasks took five minutes, 55 minutes, and 360 minutes to complete, then the representative time for one task would be 46 minutes, or the third root of 99,000 (which is 5 times 55 times 360).

Divide 60 minutes by the geometric mean to obtain the number of tasks of dissimilar duration that can be completed per hour. For example, 60 divided by 46 is 1.3 tasks per hour.
References
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