Coins

A boy gives 11 coins of equal denomination to a man, and the man finds that their total value in yen is 4 less than his age.  The boy gives the man 9 coins of equal denomination, different from before, and the man finds that their total value in yen is 5 less than his age.  What is the age of the man? 

Japan, Edo Period, 1603-1867

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