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IMSO 2004 Mathematics – Taiwan Selection – Short Answer Question 33

IMSO Maths · IMSO 2004 Mathematics – Taiwan Selection – Short Answer

Question 33

Andy always tells lies on Wednesdays, Thursdays and Fridays. On the other days, Andy is always honest. Fred always lies on Saturdays, Sundays and Mondays, and is honest on the rest of the week. One day both of them said: “I lied yesterday”. On what day did they say that?