2006 AMC 10B Problems/Problem 16

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Problem

Leap Day, February 29, 2004, occured on a Sunday. On what day of the week will Leap Day, February 29, 2020, occur?

Solution

There are days in a year, plus extra day if there is a Leap Day, which occurs on years that are multiples of 4 (with a few exceptions that don't affect this problem).

Therefore, the number of days between Leap Day 2004 and Leap Day 2020 is:

Since the days of the week repeat every days and , the day of the week Leap Day 2020 occurs is the day of the week the day before Leap Day 2004 occurs, which is .

See Also

• 2006 AMC 10B Problems

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