Let's use 150,000,000 instead and pay them a basic income of $20,800 per yr ($400 per wk, $10 per hr). That's $3.120T with a "T", just south of scheduled 2013 U.S. federal expenditures of $3.803T -- with a $900B deficit.
A BI would double federal expenditures. Honestly, how likely is it for a guaranteed basic income to pass both houses of Congress and be signed by the POTUS in the next 5, 10, or 25 years?