I'm not sure, but one stat is that a honeybee gathers enough nectar in her life to produce 1/12 of a teaspoon of honey.
Looking a tsp, but there is no way that a honeybee hold a 1/10th tsp in at a time. There are 20-30 honey drips or more in a tsp (I stopped counting at 20), and a honey drip is almost the size of a bee's abdomen.
Other than that I have have no idea, but I'd say 10,000's, many trips. But when on the hive, each trip is very short so they can take lots of trips.
And what if they are small cell bees??? :roll: