I'm guessing it means that once the first car leaves the loading area and gone one lap around and back to the top, 500 people have ridden to the top.
- youngsters and your new math
I'm guessing the Ski Fifty Years In North America publication is Colorado, Oregon, Washington or Alaska? :eyeroll:
"Two cabins, each with a capacity for 80 passengers and one attendant, travel at a speed of 1,500 feet (460 m) per minute, with an hourly passenger capacity of 1,540, or 770 in each direction, more than three times the capacity of the original tramway." (Wikip.)