The concepts are heavily covered in the training corpus, and if people were allowed to take it more than once, with even a book let alone access to the internet it wouldn't be very hard.
Examples:
1) Find the sum of all integer bases $b>9$ for which $17_b$ is a divisor of $97_b.$
In the corpus: https://www.quora.com/In-what-bases-b-does-b-7-divide-into-9...
And one more:
3) https://artofproblemsolving.com/wiki/index.php/2025_AIME_I_P...
Is just the the number of ways to distribute k indistinguishable balls (players) into n distinguishable boxes (flavors, without exclusion, in such a way that no box is empty.
Thus in the corpus for any courses that need to cover combinatorial problems including physics, discreet math, logistics etc...
IMHO these concept classes from a typical AIME are so common, the scores you gave demonstrate that those models are doing no "general reasoning" at all and are actually failing at approximate retrieval.