Absolute Advantage

$\backslash$table$[[,\backslash$table$[[$Hours needed to make $1],[$pound of:$]],\backslash$table$[[$Amount produced in $40],[$hours $($hrs$)$:$]]],[,$Meat,Potatoes,Meat,Potatoes$],[$Farmer$,20$ hrs $\frac{?}{lb},10$hrs$/$lb$,2$ lbs$,4$ lbs$],[$Rancher$,1$ hour$/$lb$,8$hrs$/$lb$,40$ lbs$,5$ lbs$]]$

The Rancher needs only $8$ hours to produce a pound of potatoes, whereas the Farmer needs $10$ hours.

The Rancher needs only $1$ hour to produce one pound of meat, whereas the Farmer needs $20$ hours.

Even if the Rancher has an absolute advantage in the production of both meat and potatoes, it is still beneficial for him to trade. Why?