Forbes' comprehensive list of the world's billionaires (there are 1226) came out recently, and we were curious -- are there women on the list?

Turns out, there are. Yes, men far outnumber the ladies. But starting at number 11, women help fill out the ranks of the fabulously wealthy.

Where do these fortunes come from? Uniformly, these top six women have shrewdly managed the companies and fortunes handed to them by husbands and fathers. But most of these women have put in their own hard work into these companies to grow them, especially the woman who is now president of Fidelity Investments. (Because women do make better investors!)

Of course, it took a few generations for these fortunes to build up, and many of the male billionaires on Fortunes' list are, well, advanced in age, having worked hard for their wealth over a lifetime. We're looking forward to a few years down the road when the list is populated by many more women and their own companies, instead of those founded by the the men in their lives.

After all, the founder of Spanx just broke into the billionaire list. Who knows what kind of riches she'll have by the time she retires?

Learn more about some of the richest women in the world:

6. Laurene Powell Jobs
Estimated net worth: $9 billion
Rank: 100th richest person in the world, 36th richest person in the U.S.
Age: 48
Why she's rich: She's the widow of Steve Jobs.
Lives in: Palo Alto, California

5. Abigail Johnson
Estimated net worth: $10.3 billion
Rank: 85th richest person in the world, 33rd richest in the U.S.
Age: 50
Why she's rich: She owns and runs Fidelity Investments with her father, Edward Johnson III.
Lives in: Milton, Massachusetts