> At the time of their marriage in 1994, Bill Gates’s fortune was worth approximately $9.35 billion.
https://www.wsfamilylaw.com/the-multibillion-dollar-gates-di...
> Gates became the world's then-youngest billionaire in 1987, at age 31.
https://en.wikipedia.org/wiki/Bill_Gates
If you had tried sourcing your claim, you would know it was wrong.