Not to come across sexist, but . . .
 

Of the 15 richest women in the world, only 2 became that way on their own merits. The other 13 became rich when their husbands/fathers died.

15 Richest Women in the World

some of them seem pretty smart !:2 cents:

Good Info! I wasn't know this.

I know I shouldn't have clicked, but didn't all of those women's men also get rich the old-fashioned way by inheriting it? First one on the list wasn't married to Sam Walton, but one of his descendants.

Fair point, but all of those businesses were started by men, even if it was 2-4 generations previous. I guess to make it fair, we should look at the top 15 richest men in the world, and see how many didn't inherit it. But I'm guessing it's way more than two.