Operations Research Exam 2 Graded A+

Operations Research Exam 2 Graded A+


Total Float - ANSWER-TF(i,j)= LT(j)-ET(i)-Tij

Critical Path - ANSWER-activities with 0 total float

Critical Path - ANSWER-the sequence of activities in a project that is expected to
take the longest to complete

Free Float - ANSWER-The amount of time that a schedule activity can be delayed
without delaying the early start date of any successor or violating a schedule
constraint.

Free Float - ANSWER-FF(ij)= ET(j)-ET(i)-Tij

PERT - ANSWER-Program Evaluation and Review Technique.

a - ANSWER-duration under ideal conditions

b - ANSWER-duration under worst case conditions

m - ANSWER-most likely duration

Expected value PERT - ANSWER-E(Tij)= (a+4m+b)/6

Variance PERT - ANSWER-V(Tij)= (b-a)^2/36

Expected time to complete a path - ANSWER-sum of all expected times for the
activities in the path.

Variance time to complete a path - ANSWER-sum of all variances for each activity
in path

Standard deviation - ANSWER-square root of variance

P(CP<=x) - ANSWER-P(CP<=x)=P(z<= (x-E(CP))/S.D)

Problems with PERT - ANSWER-Activity durations must be independent (not
realistic)
Activity durations follow beta distribution
CP stays the CP no matter what actual activity duations are