When duration is fixed, it remains at whatever value you enter and Microsoft Project calculates resource units as you change assignments. For example, say you assign two painters full-time to paint the walls in 4 days. Later, you assign two more full-time painters. Microsoft Project set the units for each painter to 50 percent, because four painters need to work only half-time to complete the walls in 4 days.
If you adjust the task’s duration, Microsoft Project calculates work. In the painting example, the total work for the task is 64 hours (four painters × 4 days × 4 hours per day). If you change the task’s duration to 2 days, Microsoft Project recalculates the total work: four painters working half-time for 2 days is 32 hours.
To change a task type
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