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Halloween Day

Age 11 to 14 Short Challenge Level:

One year, there were exactly four Tuesdays and exactly four Fridays in October.

On what day of the week did Halloween, October 31st, fall that year?


If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.

This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.