Did you get stuck in the slowest line – again?

If you’d like to pick the line in the store with the best odds of moving – there’s a formula for that...

It was developed by John D.C. Little – and it’s fairly simple. First, you’ll need to determine the average wait time in any given line. To do this, take the number of people in the line and divide that by their arrival rate. If there are six people in the line and two shoppers are joining per minute – the average wait time will be three minutes.

Long lines aren’t necessarily the worst. A single-file line leading to more than one register actually moves much faster than separate lines for each cashier. Any delay in the multiple-line system stops that line completely, while a glitch in the single-line system is only a problem for one unlucky customer.