If in 2000 there were 61,000 people living per square mile in mirpur, what is the approximate area of mirpur?

Answer: 
30 sq miles
Population Statistics Mirpur Dhaka City Population, 2003 1,933,7981 19,190,115 Population, 2000 1,822,195 18,976,457 Households, 2000 708,644 7,056,860

If in 2000 there were 61,000 people living per square mile in mirpur, what is the approximate area of mirpur?