[Half Vast Conspiracy]

U.S. census data shows that an average of 17.9% of residents lived in mobile homes from 2007 to 2011 — not 20%.

First, she didn't claim that 20% of resident live in mobile homes. She said 20% of homes were mobile.

Second, 17.9 is close enough to round up to 20%. The media would let President Obama do that kind of rounding without question.

[ClearCase_guy]

Obama talked about 57 states, and the media shruggd: “Close enough”.