Final answer:
The 1920s were known as the Roaring Twenties due to the rapid growth of the U.S. economy, transitioning from agriculture to manufacturing.
Step-by-step explanation:
The 1920s were known as the Roaring Twenties because of the rapid growth of the U.S. economy following World War I through the end of the decade. The economy shifted from being largely agriculture-based to becoming more manufacturing-based, which led to a period of prosperity and increased consumerism. This economic boom created a sense of energy and excitement, hence the term 'Roaring Twenties'.
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