One day in 1980, Jim said, "The day before yesterday I was twelve.
logic/twelve.and.fifteen New
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Problem
One day in 1980, Jim said, "The day before yesterday I was twelve. Next year I will be fifteen." What was the date when he said this, and what is his date of birth?
Show solution
No tricks, just logic. The day was 1st Jan 1980. The day before yesterday was 30th Dec 1979 - I was 12. Yesterday was 31st Dec 1979 my birthday - I was 13. This year on the 31st Dec 1980 - I will be 14. Next year on the 31st Dec 1981 - I will be 15. I was born 31st Dec 1966. -- Mark Parry <MParry@mertcplc.demon.co.uk>