To find the amount of total land fenced, note that Stan only owns 4/5 acres of a piece of a land and 2/3 acres of that piece he owns is fenced. To find the amount of Stan's land that is fenced, you would multiply 4/5, the amount he has, by 2/3, the amount fenced. This would be represented by this expression:
4/5*2/3
When it is simplified, you will get you answer as 8/15 acres of land is fenced