Hi,

very often Tasks are estimated by effort, not duration. And Tasks are fixed work type. Now the question is: “How many hours will each resource spend at the Task?”

I will show that in **MS PROJECT 2019.¸**

Let’s say that I have a Project with one Task which need effort 24 hour (I will show that in Task Usage View):

and that we have four Resources:

John is available 100%, Mary 50%, Peter 75%, and Paula 20% to work per day. So John can work max. 8 hours per day, Mary 4 hours, Peter 6 hours, and Paula 2 hours.

Now I will assign them to the Task:

So, Duration is 3 days, and each Resource will work 6 hours in Total. Let me explain the calculation:

- Since total work is 24 hours, and we have four Resources, each Resource will have to work 24 hours / 4 Resources = 6 hours
- John is 100% assigned. So according to formula Work = Duration * Units he will work 6 hours at first day, and he is done
- Mary is 50% assigned. So according to formula Work = Duration * Units she will work 4 hours at first day, and remining 2 hours at second day
- Peter is 75% assigned. So according to formula Work = Duration * Units he will work 6 hours at first day, and he is done
- Paula is 25% assigned. So according to formula Work = Duration * Units she will work 2 hours at first day, 2 hours at second day, and remining 2 hours at third day.

No, suppose that only John and Paula will work on Task:

So, Duration is 6 days, and each Resource will work 12 hours in Total. Let me explain the calculation:

- Since total work is 24 hours, and we have two Resources, each Resource will have to work 24 hours / 2 Resources = 12 hours
- John is 100% assigned. So according to formula Work = Duration * Units he will work 8 hours at first day, and remaining 4 hours at second day
- Paula is 25% assigned. So according to formula Work = Duration * Units she will work 2 hours each day, and it will take her 6 days to fulfill those 12 hours.

This might seem complicated, but once you got it, you will see it is not!

Hope this helps.

Regards