How many Americans lived in the tract homes of the modern suburbs by the end of the 1950’s

Question- How many Americans lived in the tract homes of the modern suburbs by the end of the 1950’s

Answer- For many generations and many decades, the AMERICAN DREAM has promised an EGALITARIAN society and material prosperity. For many, the notion of prosperity remained just a dream.  But for millions of Americans in the 1950s, the American Dream became a reality. Within their reach was the chance to have a house on their own land, a car, a dog, and 2.3 kids. POSTWAR AFFLUENCE redefined the American Dream. Gone was the poverty borne of the Great Depression, and the years of wartime sacrifice were over. Automobiles once again rolled off the assembly lines of the Big Three: Ford, General Motors, and Chrysler. The Interstate Highway Act authorized the construction of thousands of miles of high-speed roads that made living farther from work a possibility.  Families that had delayed having additional children for years no longer waited, and the nation enjoyed a postwar BABY BOOM.

these civilizations were located around fertile rivers, where they could produce an abundance of crops