If you need to use one or the other to arrive at the correct answer the question will tell you which one to use. In my experience I was always free to use whichever method I wanted.
If the question doesnt explicitly mentioned day 1 or day 0 to be used, what should you consider in calculations?
One way is to look at answers and find out using elimination.
But what you have answers for both day 0 and day 1 formula?
How do you calculate? Will PMI exam have such 1 day difference answer formulas?
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