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A multiplicity fraction is the fraction of a set of star systems (taking star system to mean either single or multiple stars) that have more than one individual star. A galaxy, such as the Milky Way, has a multiplicity fraction, as has a particular globular cluster, and has the set of "all G-type stars". For example, if a set of twenty individual stars is comprised of four binary stars plus twelve isolated stars, then the set's multiplicity fraction is 25% because four of sixteen systems have multiple stars. The same set of stars could be characterized by other fractions besides this defined multiplicity fraction: for example, 40% (eight of twenty) of the set's individual stars are within multiple star systems.