Library / /30 of 241

, 2023

Combinatorics Difficulty 1.2 Junior Find the answer Canada

The number 2023 is written on one side of a classroom
window using the style of numbers shown.

If you were to stand on the other side of the window, how would the
number appear?

Your answer

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

When looking at [[IMAGE0]] through a window from behind, the digits appear as mirror images
and in reverse order, and so appear as
[[IMAGE1]] .

Want a route through all this instead of an archive? The track puts 2,444 problems in a working order, from Junior Challenge level to the IMO shortlist.

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