Guillaume is 29 years old (birthdate: November 11, 1981).
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Guillaume Le Gentil was born on September 12, 1725 and died on October 22, 1792. Guillaume Le Gentil would have been 67 years old at the time of death or 286 years old today.
Guillaume Apollinaire was born on August 26, 1880 and died on November 9, 1918. Guillaume Apollinaire would have been 38 years old at the time of death or 131 years old today.
Louis Guillaume Lemonnier was born on June 27, 1717 and died on September 7, 1799. Louis Guillaume Lemonnier would have been 82 years old at the time of death or 294 years old today.