Answer
The population density is 11,941 people per square mile.
Work Step by Step
We know that 1 mile = 1 km
We know that 1 hectare = 0.01 square kilometer
We can find how many square kilometers are in 1 square mile.
$1~mi^2 = 1~mi\times 1~mi$
$1~mi^2 = 1.6~km\times 1.6~km$
$1~mi^2 = 2.56~km^2$
We can find how many square miles are in one hectare.
$1 ~ha = \frac{1~ha}{1}\times \frac{0.01~km^2}{1~ha}\times \frac{1~mi^2}{2.56~km^2}$
$1~ha = 0.00391~mi^2$
We can express the population density in units of people per square mile.
$\frac{46,690~people}{1000~ha} = \frac{46,690~people}{1000~ha}\times \frac{1~ha}{0.00391~mi^2} = \frac{11,941~people}{1~mi^2}$
The population density is 11,941 people per square mile.