Age when they started their company: Bill Gates, Microsoft: 19 Sara Blakely, Spanx: 27 Fred Smith, FedEx: 27 Doris Fisher, Gap: 37 Henry Ford, Ford: 39 Sam Walton, Walmart: 44 Jim Sinegal, Costco: 47 Gordon Bowker, Starbucks: 51 Charles Flint, IBM: 61 Colonel Sanders, KFC: 62