Reasoning
453 problems in counting, pattern-finding and figure enumeration — the groundwork the curriculum skips and competition assumes. Pick the kind of thinking to practice.
75 problems
Invariant
Spot the quantity that never changes, however you move.
Practice → 67 problems
Pattern & rule
Read the rule behind a sequence, then push it far ahead.
Practice → 64 problems
Shape enumeration
Find the triangles, squares and regions hiding inside a figure.
Practice → 62 problems
Logic
Combine clues until only one answer survives.
Practice → 62 problems
Other
Problems that do not sit in one domain yet.
Practice → 50 problems
Number arrangement
Place digits to hit the largest, smallest or exact target.
Practice → 47 problems
Counting
Count every case once — no misses, no double-counting.
Practice → 26 problems
Optimization
Search the possibilities for the best one, and prove it is best.
Practice →