Like Steve Jobs, Bill Gates and Mark Zuckerberg, Richard Branson became a billionaire without formally completing a college degree. However, one of the most important values he stands by is "to always be learning, no matter your age."
"Having an insatiable curiosity for the world around you is an essential skill as an entrepreneur," Branson wrote in a recent blog post. "This fascination comes easily to children who are still learning and find all kinds of things interesting."
Branson shared a letter he received from a young boy named Adam, who asked the billionaire five questions about Virgin and his U.K.-based train operating company Virgin Trains.
To answer Adam's first and fourth questions, Branson noted that each 11-car Pendolino, the longest fleet Virgin Trains owns, costs £11m which equals out to almost $15 million for each fleet. Branson added there are 56 Pendolino trains.
Branson wrote that he created Virgin Trains because he thought there had to be a better way of servicing customers.
"Train services were very outdated and there was a real opportunity to disrupt the market and make things better for passengers. I wanted a train company that radically changed the way people viewed and used the train," he added. "We set ambitious goals to speed up journey times with modern tilting trains, increase the frequency of the service and improve the onboard experience."
In his recently published book, "Finding My Virginity," Branson said he got the idea of running his own train company in 1991 when he rode a Japanese bullet train from Tokyo to Kyoto.
"It wasn't just the speed, as we whizzed through the Japanese countryside at 199 mph, it was also the excellent service, the vending machines, the entertainment — much of it reminiscent of the plane journeys Virgin Atlantic had pioneered," Branson said. "It made me wonder why the trains in the U.K. were so bad by comparison."
Despite his excitement, Branson faced pushback when planning to start Virgin Trains: Former British Rail CEO John Welsby's opposed Branson's ideas and the privatizations of the train rails. For example, the Pendolinos, Branson's train of choice, had the preceding reputation as "accident prone trains."
These obstacles did not prevent Branson from building an expert team of professionals to launch Virgin Trains.
Down the line, Branson got out of losing his franchise thanks to his supporters.
"There was a great campaign created and supported by our passengers and staff, who did not want to see us no longer running services along the West Coast. We couldn't thank them enough for their love and support," Branson said.
For Adam's last question, Branson jokingly deferred his full answer to the child's parents.
"This is probably a question for your parents…The name 'Virgin' was the result of a team effort. We were thinking about naming our records business 'Slipped Disc' until a young woman jokingly pointed out we were all virgins at business as it was something we hadn't done before," Branson said.
The entrepreneur wrapped up his response to Adam by telling him to keep up his curiosity.
"It's always heartwarming to see a child who is engaged in a subject and it's important to always be learning, no matter your age," Branson wrote. "The future belongs to the curious – don't be afraid to ask questions and see where your curiosity takes you."
Like this story? Like CNBC Make It on Facebook.