Under the mercantilist theory, how does the colonial role of supplying raw materials to the mother country and buying its finished products contribute to making the mother country rich?

Mercantilism was the indication that a country could only grow its prosperity by distributing more than it imported. This idea was pertinent to the way the British preserved the colonies because mercantilism also says that a colony should not be permissible to race with the mother country. The colony should take imports from the mother country, instead of manufacturing its own goods. All of the colony’s exports should go over the mother country and then be exported ahead. By this means, the payments for the exports would go to the mother country making it rich.