In a certain non-leap year, January 1st fell on a Tuesday. On what day of the week did October 1st fall in that same year?
Tuesday
The number of days from Jan 1 to Oct 1 in a non-leap year is 31 (Jan) + 28 (Feb) + 31 (Mar) + 30 (Apr) + 31 (May) + 30 (Jun) + 31 (Jul) + 31 (Aug) + 30 (Sep) = 273 days. 273 divided by 7 is exactly 39 weeks with a remainder of 0. Thus, Oct 1 falls on the same day of the week as Jan 1.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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