How Bet365's Denise Coates Hit her Own Jackpot ByRebecca Marston Business press reporter, BBC News Denise Coates, the billionaire boss of Bet365, added another ₤ 323m to her wealth today after the company her family founded acquired another year of big profits. She's been called the UK's most effective female, with a fortune that Forbes magazine puts in the area of ₤ 9.3 bn. Most noticeably, she has made that mainly herself. Bet365 is Stoke-on-Trent's largest personal sector employer, with more than 4,600 personnel. It offers its countless worldwide consumers sports betting, poker, gambling establishment, games and bingo. The firm had a ₤ 3bn turnover in the year to the end of March and a profit before tax of ₤ 791m. Ms Coates' brother John is joint chief executive and her father Peter is the firm's chairman, but Denise Coates owns half the business and there's no doubt the success is mostly hers. LISTEN: Profile: Denise Coates Bet365 employer sees pay rise to ₤ 265m Serious gamblers tend to have a "system", an allegedly sure-fire method that will keep bringing rewards. So what's her "system"? Go back to the 1990s and there aren't many who would have bet on the little family-run chain of regional betting shops growing to such a size. A lot is down to her mathematical skill, which was remarkable from an early age. David Owen taught her at secondary school in the 1980s. "She got everything right, just asked pertinent questions and was angelically behaved. She was plainly off the scale. If we were talking Mensa, she 'd remain in the leading 1%," he informed the BBC. 'More women' She attained a superior degree in econometrics and trained as an accountant within the family firm, building further on the understanding of the little chain that she got while working part-time during high school.