There is no easy answer to this question. Depending on the amount of investment made behind a business, the profits can vary. For example, Youtube was worth 4.6 Billion Dollars when Google bought it off. Now it stands at 160 Billion Dollars. Even if we chalk it up as a profitable business, most people will not have the finances required to start a business as such. But if we are looking to get a ballpark idea, we can say that Restaurant businesses, Real Estate, Fashion, Transportation, and Medical Services will turn out to be profitable. This is because the increasing population in the world increases the demands of the people's basic needs such as Food, Accommodation, Clothing, and Treatment.