FORWARD PASS AND BACKWARD PASS

ACTIVITY

ES

EF

LS

LF

SLACK

CRITICAL

A

$0$

$4$

$0$

$4$

$0$

YES

B

$0$

$3$

$1$

$4$

$1$

C

$4$

$9$

$4$

$9$

$0$

YES

D

$3$

$7$

$6$

$10$

$3$

E

$9$

$13$

$9$

$13$

$0$

YES

F

$13$

$20$

$14$

$21$

$1$

G

$13$

$19$

$13$

$19$

$0$

YES

H

$20$

$24$

$21$

$25$

$1$

I

$7$

$16$

$10$

$19$

$3$

J

$19$

$25$

$19$

$25$

$0$

YES

CRITICAL PATH $=$ A$--$C$--$E$--$G$--$J

DURATION OF CRITICAL PATH $=25$

Explanation:

ES $=$ Max$($EF Of All Predecessors$)$; $0$ For The First Activity

EF $=$ ES $+$ Duration

LF $=$ Min$($LS Of All Successor Activities$)$; Max EF As LF For Last Activity

Slack $=$ LF $-$ EF or LS $-$ ES

Critical Path $=$ Longest Path With $0$ Slack