Path mean Path time Specified z A C E Z24 2051118313 PZ31309991 D F G Z24

# Path mean path time specified z a c e z24 2051118313

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Path mean Path - time Specified = z A-C-E Z=(24 - 20.5)/1.118=3.13 P(Z<3.13)=0.9991 D-F-G Z=(24 - 21.5)/1.344=1.86 P(Z<1.86)=0.9686 B-H-I Z=(24 - 19.5)/0.726=6.19 P(Z<6.19)=1.0000 Z 24 Probability A-C-E Z=(21-20.5)/1.118 =0.45 P(Z<0.45) =0.6736 D-F-G Z=(21-21.5)/1.334 =-0.37 P(Z<-.37) =0.3557 B-H-I Z=(21-19.5)/0.726 =2.07 P(Z<2.07) =.9808 Z 21 Probability What is the probability that the project can be completed in 21days or less ? ( 29 2 2 6 - = o p t t σ Probability=.6736 x.3557 x .9808 = 0.235 Probability=0.9991*0.9686*1=0.967 5 7/819 c. Suppose it is now the end of the seventh day and that activities A and B have been completed while activity D is 50 percent completed. Time estimates for the completion of activity D are 5,6 and 7. Activities C and H are ready to begin. c. On the 8th day, the network could be reviewed as follows: 1 5 3 7 8 6 e (6.33) f (6) d (6) g (3.5) i (6.83) h (4.17) c (8.17) 8 th day *Assume it is the beginning of the 8th day Replace d by d and merge nodes (2) and (4) with (1). d : te = 6: σ 2 = 4/36 7 days were used to complete activities a, b and one half of d. In the modified network Path Expected Duration from 8th day Expected duration from the start of the project Varia nce 1 . c–e 14.50 14.50 + 7 = 21.5 41/36 2 . d f–g 15.5 15.5 + 7 = 22.5 33/36 3 . h–i 11 11 + 7 = 18 10/36 6 Path Standard Dev. Z 24 Probability (24) 1. c–e 1.0672 24 – 21.5 = 2.343 .9904 1.067 2 2. d –f–g 0.9574 24 – 22.5 = 1.567 .9418 0.957 4 3. h–i 0.5270 24 – 18 = 11.384 1.0000 0.527 .9904 x .9418 = .9328 Path Z 21 Probability (21) 1. c–e 21 – 21.5 = –0.469 0.3192 1.0672 2. d –f–g 21 – 22.5 = –1.567 0.0582 0.9574 3. h–i 21 – 18 = 5.692 0.527 .3192 (.0582) = 0.0186 7 1 4 3 2 5 6 7 8 9 10 11 3.00 2.00 6.00 5.00 7.00 2.00 3.00 4.00 5.00 4.00 6.83 0.00 3.00 0.00 3.00 1 6.00 8.00 3.00 5.00 2 8.00 11.00 5.00 8.00 5 3.00 9.00 3.00 9.00 3 9.00 11.00 9.00 11.00 6 11.00 15.00 11.00 15.00 8 4.00 9.00 3.00 8.00 4 9.00 16.00 8.00 15.00 7 16.00 20.00 15.00 19.00 10 15.00 20.00 15.00 20.00  #### You've reached the end of your free preview.

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