Given is a PERT project network diagram as shown below Activ

Given is a PERT project network diagram as shown below Activity Start A B C D E F G H I J K Time 0 10 4 13 9 7 7 4 12 7 20 15 0 a) The Project Completion time = b) The Earliest Start time, ES, of Activity F = c) The Earliest Start time, ES, of Activity K = d) The Latest Start time. LS. of Activity E = e) The non-critical activities are = (ex. type in critical activities as ABCD, no comma, no space)

Solution

In the Pert alternate paths are given.

b) Earliest start time F =

This asks us to select starting F in the least time.

There are 3 roots for starting F, AF or BEF or CDEF

OF these we have to select one which has minimum time. As start time of F, we do not add time for F

AF = 10

BEF =11

CDEF = 29

Hence earliest activity for F = 10

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c) For K

AFHK = 29

Obviously this will be minimum as AF is the earliest root

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Latest start activity for E

CDE =22

BE =4

Hence latest is CDE =22

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e) The non critical activities mean where the roots are not more than 1

A, I, B, C, J, H, K,D

a) Project completion time is

AFHK = 44 or

BEFHK = 45 or

AGIK = 36 or

CDEGIK = 55

CJ = 33

Thus earliest is CJ

and longest is CDEGIK