The expected time \(t_e\) of a PERT activity in terms of optimistic time \(t_o\), pessimistic time \(t_p\), and most likely time \(t_l\) is given by

\(t_e = (t_o + 4t_l + t_p)/6\)
\(t_e = (t_o + 4t_p + t_l)/6\)
\(t_e = (t_o + 4t_l + t_p)/3\)
\(t_e = (t_o + 4t_p + t_l)/3\)

Correct answer: \(t_e = (t_o + 4t_l + t_p)/6\)

Solution

In PERT, the expected time is computed as a weighted average of optimistic, most likely, and pessimistic times. The standard formula is \(t_e = (t_o + 4t_l + t_p)/6\).

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