Final answer:
The exact age William Levitt was when he took over the family company is not provided, but he is known for revolutionizing house building post-World War II and creating suburbs with affordable homes for many Americans, particularly veterans.
Step-by-step explanation:
The specific age at which William Levitt's father put him in charge of running their company is not detailed in the provided information. However, we know that William Levitt became an influential real-estate developer who pioneered the mass-production of houses, leading to the creation of suburbs like Levittown. After World War II, Levitt applied his efficient mass-production techniques to residential construction, which were greatly assisted by provisions such as the GI Bill and loans from the Federal Housing Administration. These enabled many Americans, especially veterans, to afford homes by reducing down payments and monthly payments to manageable amounts. The construction teams could build homes quickly by having specialized teams performing set tasks in an assembly-line fashion.
Levitt's business approach and his controversial policies, such as racially restrictive covenants, have had a significant impact on American suburbia and housing policy. His legacy includes accelerating the trend of suburbanization and the accessibility of homeownership in post-war America, despite the racial discrimination practiced in his developments at that time.