Final answer:
A PR electoral system is used in countries with a multiparty system to ensure fair representation, and it often leads to the formation of coalition governments.
Step-by-step explanation:
A PR electoral system is a type of electoral system that aims to ensure that the number of seats a political party receives in the legislature is proportional to the number of votes it receives from the electorate. This system is commonly used in countries with a multiparty system, where multiple political parties have a significant presence in the legislature. When no single party has a clear majority, a coalition government is often formed, where multiple parties join together to govern.