Due to an influx of spam in our forums we have disabled posting for guests. Guests can still read the forum, but you have to login in order to start or participate in a discussion.
Welcome, Guest
Do you need customer support or technical assistance? Click here to submit a support ticket...

TOPIC: Why is this the correct answer?

Why is this the correct answer? 2 years 5 months ago #4589

  • SANDHYARANI P BHIDE
  • SANDHYARANI P BHIDE's Avatar
  • Offline
  • Fresh Boarder
  • Posts: 4
  • Thank you received: 1
  • Karma: 0
Hi,

I don't understand how this answer was calculated for the question from Oliver Lehmann's free 75 question test.
Can anyone please enlighten? The correct answer is B ie. approx. 5.2 days.

27. A project manager made 3-point estimates on a critical path and found the following results: (Check attached table below)

Assuming ±3 sigma precision level for each estimate, what is the standard deviation of the allover path?

(A) App. 4.2 days
(B) App. 5.2 days
(C) App. 6.2 days
(D) You can not derive the path standard deviation from the information given.
Attachments:
The administrator has disabled public write access.

Why is this the correct answer? 2 years 3 months ago #4774

  • Ivan Fućak
  • Ivan Fućak's Avatar
  • Offline
  • Fresh Boarder
  • Posts: 1
  • Karma: 0
You can use following link for calculation:
www.firebrandtraining.co.uk/learn/pmp/co...e-activity-durations
You have to calculate standard deviation for each activity.
(24-12)/6=2,
(14-8)/6=1,
(27-15)/6=2,
28-10)/6=3,
(35-17)/6=3
Variances of each activities are squares of deviations of activities.
Stand.deviation of path is square root of sum of variances:
SQRT(4+1+4+9+9)=SQRT(27)=5,19
The administrator has disabled public write access.

Why is this the correct answer? 7 months 1 week ago #7772

  • Mohammed Yaseen
  • Mohammed Yaseen's Avatar
For +_ 3 Sigme, the standard deviation = 3 * Standard Deviation of 1 Sigma prceision level.

So in this case, the standard deviation should be = 3 * 5.19 = 15.57

Hope, I am right.
If not, PLEASE explain me.
The administrator has disabled public write access.

Why is this the correct answer? 3 months 1 week ago #8918

  • shravan
  • shravan's Avatar
Waw...Super..I got it...thanks a lot...dint understand logit behind t ...but doesnt matter
The administrator has disabled public write access.

Why is this the correct answer? 3 months 1 week ago #8926

  • Hazem Ibrahim
  • Hazem Ibrahim's Avatar
  • Offline
  • Senior Boarder
  • Posts: 58
  • Thank you received: 2
  • Karma: 0
please note that putting ±3 sigma precision level in the question is meaningless and useless it is just to scatter you away
The administrator has disabled public write access.
Moderators: Yolanda Mabutas, Ahmed Amin, Scott Gillard, Michael DeCicco, Rahul Kakkar, Fernando Jr Sinlao Lim, Mary Kathrine Padua, Chris Preziotti, Lazard Toe, ITBMC, MPM, CIPM, PMP, ITIL, Christian Winter, Kevin Nason, Michael Sumaquial, PMP, Mark Wuenscher, PMP

OSP INTERNATIONAL LLC
OSP INTERNATIONAL LLC
Training for Project Management Professional (PMP)®, PMI Agile Certified Practitioner (PMI-ACP)®, and Certified Associate in Project Management (CAPM)®