Maths Olympiad Prep

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, 2024

Algebra Difficulty 4.9 AIME Find the answer United States

Problem:

Let pp denote the proportion of teams, out of all participating teams, who submitted a negative response to problem 5 of the Team round (e.g. "there are no such integers"). Estimate P=10000pP=\lfloor 10000 p\rfloor. An estimate of EE earns max(0,20PE/20)\max (0,\lfloor 20-|P-E| / 20\rfloor) points.

If you have forgotten, problem 5 of the Team round was the following: "Determine, with proof, whether there exist positive integers xx and yy such that x+y,x2+y2x+y, x^{2}+y^{2}, and x3+y3x^{3}+y^{3} are all perfect squares."

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

Solution

Solution:

Of the 88 teams competing in this year's Team round, 49 of them answered negatively, 9 (correctly) provided a construction, 16 answered ambiguously or did not provide a construction, and the remaining 14 teams did not submit to problem 5. Thus p=49880.5568p=\frac{49}{88} \approx 0.5568.

Want a route through all this instead of an archive? The track puts 2,000 problems in a working order, from AMC 10 level to the IMO shortlist.

Source: MathNet, licensed CC-BY-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.