Suppose Mars needs 24 million Martians to produce 1 starship per year and it needs 4 million workers to make 1 trillion tons of food per year.

Venus only needs 2 million Venusians to make a starship and 2 million workers to make a trillion tons of food.

Suppose each planet has 48 million people and dedicates half of workers to each sector.

The most the Martians can produce without trade is 2 starships or 12 trillion tons of food.

The most the Venusians can produce without trade is 24 starships or 24 trillion tons of food

Suppose that Martians specialize in making food and produce 12 trillion tons per year and the Venusians specialize in starships and make 14 starships per year and 10 trillion tons of food. Suppose further that the Venusians trade 1 starship for 3 trillion tons of food.How much richer does this trade make the Galaxy?