Sir John Major is 67 years old (birthdate: March 29, 1943).
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Sir John Soane was born on September 10, 1753 and died on January 20, 1837. Sir John Soane would have been 83 years old at the time of death or 258 years old today.
Sir John Pritchard was born on February 5, 1921 and died on December 5, 1989. Sir John Pritchard would have been 68 years old at the time of death or 91 years old today.
Sir John Monash was born on June 27, 1865 and died on October 8, 1931. Sir John Monash would have been 66 years old at the time of death or 146 years old today.