For a PERT activity, the optimistic time is 6 minutes, the most likely time is 9 minutes and pessimistic time is 16 minutes. The expected time of the activity (in seconds) is

Correct option is D

​$$\begin{aligned}&\textbf{Given:} \\&t_o = 6 \text{ minutes (Optimistic time)} \\&t_m = 9 \text{ minutes (Most likely time)} \\&t_p = 16 \text{ minutes (Pessimistic time)} \\[1em]&\text{The expected time } t_e \text{ in PERT is given by the weighted average formula:} \\&t_e = \frac{t_o + 4t_m + t_p}{6} \\[1em]&\text{Substitute the values:} \\&t_e = \frac{6 + 4(9) + 16}{6} = \frac{6 + 36 + 16}{6} = \frac{58}{6} \approx 9.667 \text{ minutes} \\[1em]&\text{Convert to seconds:} \\&t_e = 9.667 \times 60 \approx \boxed{580 \text{ seconds}}\end{aligned}$$​​