Drew Houston found success at a pretty young age.
The 33-year-old billionaire founded Dropbox, the file-sharing and storage service, at age 24. In January 2014, after his company was valued at $10 billion, Houston joined Forbes' billionaire ranks, where he still holds a spot today.
But in a recent interview with Adam Bryant of The New York Times, Houston said that he told students in his 2013 commencement speech at MIT, his alma mater, that if he had a cheat sheet he could give himself at 22, it would have three things on it: "a tennis ball, a circle, and the number 30,000."
The tennis ball, he said, is about finding the thing you're infatuated with.
"The most successful people and successful entrepreneurs I know are all obsessed with solving a problem that really matters to them," Houston explained. "I use the tennis ball for that idea because of my dog, who gets this crazy, obsessed look on her face when you throw the ball for her."
The circle, meanwhile, is about the idea that "you're the average of your five closest friends, so make sure to put yourself in an environment that pulls the best out of you."
And lastly, the number 30,000 is about making the most of your life.
He said: "When I was 24, I came across this website that says most people live for about 30,000 days. So you have to make every day count."
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