Problems

Operations, place value and order of operations under contest pressure.

Divisors, remainders, primes and digit structure.

Setting up and solving with unknowns instead of guessing.

Speed, work, percent and proportional reasoning.

Angles, area and length in the plane.

Solids, surface area, volume and what a net folds into.

Count every case once — no misses, no double-counting.

Favourable cases over total cases, and when that is not enough.

Read the rule behind a sequence, then push it far ahead.

Combine clues until only one answer survives.