2012 AMC 12A Problem 9
Below is the professionally curated solution for Problem 9 of the 2012 AMC 12A, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2012 AMC 12A solutions, or check the answer key.
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Difficulty rating: 1540
9.
A year is a leap year if and only if the year number is divisible by (such as ) or is divisible by but not by (such as ). The th anniversary of the birth of novelist Charles Dickens was celebrated on February a Tuesday. On what day of the week was Dickens born?
Friday
Saturday
Sunday
Monday
Tuesday
Solution:
From February to February there are ordinary days plus one for each leap day.
One quarter of the years contain a leap day, except giving leap days. So the span is days.
Since the birth day was days before a Tuesday, which is a Friday.
Thus, the correct answer is A.
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