Answer
0.43
Work Step by Step
Proabability=$\frac{Number\,of\,favourable\,outcomes}{Total\,number\,of\,possible\,outcomes}$
$=\frac{Number\,of\,males\,in\,America\,living\,alone}{Total\,number\,of\,Americans\,living\,alone}=\frac{12.5\,millions}{29.3\,millions}=0.43$