Many wealthy people can trace their successful beginnings to their 20s. After all, your 20s are typically the time when you'll experience exciting life changes, such as graduating from college, getting your first job and living on your own. But, it's also the age where you'll learn hard lessons, including how to deal with rejection or how to survive on a small paycheck.
If you're a millennial, these success stories might inspire you. From Oprah Winfrey to Mark Cuban, click through to see what these millionaires — and billionaires — were doing in their 20s.
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