Greensboro, North Carolina is 4,349,563 times larger than Jackson, Mississippi.
Area: 326 km2 calculated
Greensboro is a city in the U.S. state of North Carolina. It is the third-largest city by population in North Carolina and the largest city in Guilford County and the surrounding Piedmont Triad metropolitan region. According to the 2012 U.S. Census Estimate, Greensboro's population is 277,080. Wikipedia
Area: 0 km2 calculated
Jackson is the capital and since 1944 the largest city of the U.S. state of Mississippi. Located south of the Yazoo River, it is considered to be at the southern border of the Mississippi Delta and is one of two county seats of Hinds County, with the city of Raymond being the other. Wikipedia