What do 8 billion people do with 50 billion tons of bananas? Seems like most sources in Google are citing ~115 million tons of bananas produced per year a few years ago.
Take a look at the report you linked to, it's the one I used: "Approximately 50 billion tonnes of Cavendish bananas are produced globally every year."
Yes, other sources are taking between 80 to 115 million, but if I have to choose the UN over National Geographic, I'm choosing the UN source. though I acknowledge that the UN could still have had a typo.
http://www.fao.org/economic/est/est-commodities/bananas/bana...