Maths Olympiad Prep

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, 2025

Number theory Difficulty 1.3 Junior Find the answer Canada

The month of June has 30 days. If in a certain year June 1 is on
a Tuesday, on which day of the week is June 30?

Pick one

Solution

There are 77 days in a week.
If June 11 is a Tuesday, then by
moving successively 77 days later in
the month, we get June 88, 1515, 2222, and 2929 are also Tuesdays. Thus, June 3030 is a Wednesday.

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.