I'm looking at the formulas here: http://www.cs.auckland.ac.nz/courses/compsci742s2c/lectures/p-q.pdf
It has one for r-th percentile of waiting time ($r$% of customers wait less than said time), and another one for r-th percentile of time in queue. But if the customers are in the queue, then aren't they waiting?
The formulas:
- $\pi_w(r) = E(w)\log_e\frac{100}{100 - r}$
- $\pi_q(r) = E(w)\log_e\frac{100\rho}{100 - r}$