Language Point 20

Fish farming is very efficient: producing a kilogram of fish utilizes less than 2 kilograms of feed, but it takes 2.2 kilograms of feed to produce 1 kilogram of chicken. (Para. 8)

Meaning: Fish farming costs less but makes more profit: producing one kilogram of fish uses less than two kilograms of feed while producing one kilogram of chicken uses 2.2 kilograms of feed.