Regarding the story yesterday (Oct 15th) about a 50 lb boy being lifted by a home-made helium balloon: Ok, here's my math: The volume of an oblate spheroid that's approx 20'x3' = 17.79 cubic meters ( http://bit.ly/2cv4Ac ). According to How Stuff Works, one liter of helium can lift one gram. Which converts to 22,650 liters of helium to lift a 50 lb boy. Wolfram alpha says that 22,650 liters = 22.65 m^3 (cubic meters), meaning that the balloon could've only lifted about 39.27 lbs *IF* it was: Fully inflated (which it didn't seem to be), at sea-level (which it wasn't) and we disregard everything about air density and the temperature of the air (which was warm yesterday in Ft. Collins around the time of launch). Just for fun, I did the calculation in regular balloons, and not including the weight of the balloons or the string, it would take approx 1600 balloons to lift the 50 lb boy at sea-level. and about 1800 balloons in Colorado. :)

Now, can you calculate the amount of money that would've been saved if this calculation has been performed before the huge rescue effort started? I'll leave that as an exercise for the reader. :)