MIKE ADENUGA

Mike Adenuga was born on April 29, 1953, in the historic city of Ibadan to Michael Agbolade and Omoba Juliana Oyindamola Adenuga. The millionaire businessman worked as a cab driver to pay for his studies and support himself in the United States. Don't get me wrong. Adenuga's parents were both prosperous; his father was a teacher, and his mother was a wealthy merchant. The Globacom CEO, on the other hand, did not match the stereotype of a child born with a silver spoon.

Mike Adenuga became a billionaire at the age of 26 by marketing Coca-Cola and selling lace materials in Africa after graduating from school in the United States. He also proved to be a tenacious entrepreneur, earning his first million at the age of 26 in 1979. He hasn't stopped since then. He dabbled in a variety of enterprises, from oil and gas to telecoms, and prospered.

His firm, Conoil Producing, is currently the country's largest oil and gas company, producing around 100,000 barrels of oil per day. He also controls Globacom, Nigeria's second-largest mobile phone company, with over 15 million members. Mike Adenuga, 58, rose from 595th position in 2011 to 248th place in Forbes rankings in a year, more than tripling his fortune to $4.3 billion. Adenuga, the second richest person in Nigeria is also the 6th richest of the richest people in Africa.

Net worth: $6.7 billion

Industry: Diversified

Country: Nigeria