PMIRMP Math Formulas
All What you need to know to guarantee all math questions in the PMIRMP exam, Written based on my personal experience .
By Shadi AlSha’er , PMP® , RMP® , PRINCE2 Practitioner ®, December,02,2018
For the PMIRMP exam, you must know how to correctly answer questions with formulas about earned value, communications, procurement, expected monetary value, network diagrams, Contingency Reserves and Decision Tree Analysis. Now it’s the time to revisit the following topics, memorize their formulas for the exam and practice some questions:
 Activity Cost & Duration Estimates: Simple Average, Weighted Average, Standard Deviation and activity range of estimate .
 Critical Path Method: Early Start, Early Finish, Late Start and Late finish , Float calculations , Critical path determination .
 Earned Value Management: Cost and Schedule Variances , Cost and Schedule Performance Indexes , the 4 formulas of Estimate at Completion , Estimate to Complete , To Complete performance Index and Variance at completion .
 Numerical Risk Analysis: Expected Monetary Value , Decision Tree analysis , Contingency Reserve Calculations .
 Communication Channels : Communication Channels Formula
 Contracts Management: Make/Buy Analysis ,
You will see different question models testing your knowledge in the PMIRMP Math Formulas, Questions that is straightforward questions where you are given values and are expected to apply the correct formula , Questions were you get a set of values and asked to calculate a result. At first these look as if you can simply apply one formula. But as you are applying this first formula you suddenly realize that one value is missing. This missing value must then first be calculated via a second formula , so in such type of questions you need to apply two formulas , In some type of questions you need to invert the formulas , For instance instead of asking “2+8=?” the question would be “2+?=10” and it is your job to invert the formula and calculate “102=8 , Specially for the earned value management questions you will be given the result of the formula ( Eg : Cost & Schedule Variance ) and you will be asked “ What does this result mean for the project?” , one of the complex questions you will see for the Estimate at Completion is to select the right formula you need to use in the scenario described in the question , also you will see questions testing your knowledge in the definition of each formula , it’s not only about memorizing the formula were numbers need to be inserted , you need to understand the definition of each formula !
What’s my advise ? Practice , Practice , Practice !
Below am listing the important formulas you need to MEMORIZE for the exam !
Practice Math Questions as much as possible, you can guarantee 10% of the exam questions , expect to see around 1015 questions only on math formulas .
I have prepared a course on Udemy which was above the students expectations with more than 300 enrolled and a rating of 4.8, it contains 4.5 hours of recorded videos, going through each of the 6 topics and all math formulas included, In this course I will be solving with you 50+ exam questions, I recommend in it to master the mentioned above topics and formulas , you can enroll here for 19.99$ ( Skip the project selection methods section for the PMIRMP exam ), an additional course about the risk analysis math only can be purchased here for $9.99 only .
Topic  Term  Definition  Formulas 
Activity cost/duration estimates  Simple Average / Triangle Distribution  Gives same weight for each of the three points estimates

(P+M+O ) / 3
P = Pessimistic O = Optimistic M= Most Likely 
Weighted / Beta Average  Gives stronger consideration to the most likely estimate  (P+4M+O) /6
P = Pessimistic O = Optimistic M= Most Likely 

Standard Deviation (SD)  The possible range of the estimate, the greater the range created by the standard deviation calculation , the greater the risk .  (PO)/6
P = Pessimistic O = Optimistic 

Range of Estimate  A range of the estimate starts with EADSD and ends with EAD+SD

Range of estimate EAD ± SD
EAD : Expected Activity Duration 

Critical Path Method  Float  The amount of time an activity can be delayed without delaying the project end date or project milestone.  Float = LS – ES
= LF – EF ES : Early Start EF : Early Finish LS : Late Start LF : Late Finish

Earned Value Management

Cost Variance (CV)  Cost difference between planned and actual , target value is 0 , positive is good , Negative is bad  = EV – AC
EV : Earned Value AC : Actual Cost 
Schedule Variance (SV)  Schedule difference between planned and actual , target value is 0 , positive is good , Negative is bad

= EV – PV
EV : Earned Value PV : Planned Value 

Cost Performance Index (CPI)  Ratio of planned to actual costs , target value is 1 , greater than one is good , less than 1 is bad

= EV/AC
EV : Earned Value AC : Actual Cost 

Schedule Performance Index ( SPI )  Ratio of planned to actual schedule, target value is 1 , greater than one is good , less than 1 is bad

= EV/PV
EV : Earned Value PV : Planned Value 

Estimate At Completion (EAC)

As of today, How much we expect the total project to cost?


EAC , Formula 1  This formula calculate the actual costs to date plus a new estimate for the remaining work . It is used when the original estimates assumptions are no longer valid  = AC + ETC
AC : Actual Cost ETC : Estimate To Complete 

EAC , Formula 2  This formula is used if there is no variances from BAC .have occurred or you will continue in the same rate of spending.  = BAC / CPI
BAC : Budget At Completion CPI : Cost Performance Index 

EAC , Formula 3  This formula calculate the actual costs to date plus remaining budget , it is used when current variances are through to be atypical of the future , It is the actual cost plus the remaining value of work to perform  = AC + ( BACEV)
AC : Actual Cost BAC : Budget At Completion EV : Earned Value 

EAC , Formula 4  This formula calculates actual to date plus the remaining budget modified by performance , It’s used when current variances are though to be typical of the future and when the project schedule constraints will influence the completion of the remaining efforts

= AC + ( BACEV)/(CPI*SPI)
AC : Actual Cost BAC : Budget At Completion EV : Earned Value CPI : Cost Performance Index SPI : Schedule Performance Index 

Estimate To Complete ( ETC)  How much more will the project cost?

EAC – AC
EAC : Estimate At Completion AC : Actual Cost 

Variance At Completion (VAC)  As of today , how much over or under budget do we expect to be at the end of the project

BACEAC
BAC : Budget At Completion EAC : Estimate At Completion 

To Complete Performance Index (TCPI)  The Formula divides the work remaining to be done by the money remaining to do it .The only index with below 1 is good , above 1 is bad !!  = ( BACEV)/(BACAC)
BAC : Budget At Completion AC : Actual Cost EV : Earned Value


Risk Analysis  Expected Monetary Value (EMV)  While you are evaluation a risk you will look at the probability or impact, but calculating the expected monetary value is a better measure to determine an overall ranking of risk .

= P * I
P: Probability I: Impact

Communication  Communication Channels  Simple Concept , For each added stakeholder there should be increase in the number of communication channels  = N(N1) / 2
N : Number of Stakeholders 
If you are welling to pass the PMIRMP exam from your first attempt, this is a topic you cannot ignore! as i mentioned earlier, the PMPIRMP math questions will have a share of around 1015 questions, you need to memorize and understand all math formulas required, for a comprehensive explanation of the PMIRMP math concepts and questions, you can enroll for my PMIRMP detailed math concepts here .
Do not hesitate to contact me for guidance and help preparing for the PMIRMP exam on info@eliteminds.co