The Knave of Hearts tells only the truth on Mondays, Tuesdays, Wednesdays and Thursdays. He tells only lies on all the other days. The Knave of Diamonds tells only the truth on Fridays, Saturdays, Sundays and Mondays. He tells only lies on all the other days. On one day last week, they both said, "Yesterday I told lies."
On which day of the week was that?
Select one option, then click Submit.
Sunday
Monday
Tuesday
Thursday
Friday
Select an option, then submit.
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Senior Mathematical Challenge 2015 (2015)
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