What new invention made by Eli Whitney would do the work of 50 people turn a huge profit and bring economic growth to the south

The invention made by Eli Whitney that fits this description is the cotton gin. The cotton gin was a machine that quickly and efficiently separated cotton fibers from their seeds, drastically reducing the time and labor required to process cotton. This invention revolutionized the cotton industry in the South, making it much more profitable and leading to economic growth in the region.