Richard Branson didn't understand the difference between two business terms for years. When a colleague finally set him straight, it taught him an important lesson about strengths and weaknesses.

Like a lot of entrepreneurs, Branson never pursued formal business education. A dyslexic, he dropped out of school at 16 to run his first company. That hustle and vision eventually led to a slate of successful companies.

As he ran his businesses, he learned on the job. Still, some business terminology was never completely clear to the founder. "I've been running the largest group of private companies in Europe, but haven't been able to know the difference between net and gross," he said with a laugh during a TED talk. "So board meetings have been fascinating."

Net profits are a company's earnings minus its expenses and gross profit is a company's total earnings.

Branson hid that he didn't know the difference for years, he said in a 2010 interview with the Financial Times when answering the question "Have you ever lied at work?"

While he thought he'd hid it well, his confusion was obvious to those attending board meetings when he'd ask if the numbers presented meant good news or bad news. Finally, around 18 years ago, an executive took him aside for a lesson.

Branson's colleague drew a diagram of a net in the sea to help him grasp the concept. The fish in the net were profits left over. The fish not in the net were the gross. With his colleague's help, Branson "finally worked it all out," he said. At the time, Branson was in his 50s.

"If I'm not interested in something, I just don't grasp it," Branson said. "As somebody who's dyslexic, you often have some bizarre situations."

Though his dyslexia made some teachers think he was lazy while in school, Branson says his dyslexia helped him think creatively and to simplify complicated topics. This "has been a huge asset when building our Virgin businesses," he wrote on his blog.

His dyslexia also encouraged him to delegate and lean on experts who knew topics such as finance better than he did. This is an essential skill since entrepreneurs must learn to delegate in order to grow, he writes in a blog post.

"I was never great with numbers, so rather than do the job badly, I found [Virgin Group's first accountant] Jack," he said.

Branson knew to put his focus on areas that were more critical to his vision of success. "What matters in business is that you can create an airline that people actually want to fly on," he wrote.

Still, it's important to ask for help, no matter the topic. If you're honest with yourself, you can learn a lot, Richard Branson wrote recently on his blog. "There's no shame in admitting the places where you may fall short, and engaging with people who can help," he writes.

This article has been updated to clarify that he hid the fact he did not know the difference between the two terms.

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