$3000/person is around or larger than the world's median individual annual income: https://www.givingwhatwecan.org/post/2016/05/giving-and-glob... .

I'd also expect the total wealth among the 100 billionaires to be well over 100 billion, considering just Ellison + Zuckerberg + Page together have over 100 billion.

In a similar vein to these two figures, the richest 62 people in the world hold as much money as the poorest 50% of the world: https://www.theguardian.com/business/2016/jan/18/richest-62-... . As a direct consequence, if these 62 people gave all of their money (except for a couple million each) away immediately, 50% of the world would have twice as much money.

(edit: I'm not suggesting that billionaires instantly give all their money away as a direct cash transfer. Just providing a counterargument to "billionaires don't have that much power")