TOPIC: Question on Network Diagram

I have recently purchased the PMP® Exam Formula Study Guide, which is helping me to identify gaps.
My question is on Network Diagram, while many claims the first activity early start can neither be 0 or 1 & the corresponding results will be the same on either methods. Iam following to adapt 0 days for easy calculation.Which is the correct method & easy to understand?
I would like to mention the one of the question & answer provided in your kit.
Question : The activity “Ship Container” in your network diagram has an early
start of day 17, a late start of day 22 and a late finish of day 37. What is the activity duration?
A.) 15 days
B.) 16 days - Correct Answer
C.) 59 days
D.) 14 days

Based on the Formula guide the formula says Activity Duration=EF - ES + 1 or LF - LS + 1..when translated AD= 37-22+1 = 16. Since iam following "0" to be the ES of my activity my answer would be 15.

This may be the most silly question, but kindly clarify.

Please can anybody answer the question because I am also confusing.

Rita follows 0 start and you follow 1 start. What is the correct for the exam?

Thank you

Please read the explanation about 0 / 1 start date in our knowledge base at the following URL:

www.pmhelpdesk.com/entries/20346821-why-...ting-es-ef-ls-and-lf

I have same confusion and infact our confusion are correct as illustrated by your example we get different answers by different methods which means one of the method is incorrect.
-Sagar

I would say no formula is needed for that .. say if you start your activity at day 1 and finish on day 1 .. duration will be 1 day not 0 day. So you have to add a day if you use subtraction method.

I would say what PM Prep Case suggested is right.