(CNN) Robert F. Smith lifted a huge burden off the graduating class of Morehouse College when he announced during his commencement speech that he would pay off the student loan debt of more than 300 students.

The exact amount to be covered for the 396 students is still being calculated, Morehouse President David A. Thomas told CNN on Monday, but the figure will likely be in the tens of millions of dollars.

Here's what you need to know about the 56-year-old billionaire investor.

How he made his billions

Smith is the richest black person in the United States, with a net worth of $5 billion, according to Forbes. Yes, he's richer than Oprah.

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