Four skills, one section: spotting the hidden relationship in an analogy, sorting the odd one out, cracking a letter code, and finding the rule in a series. Every one of them rewards a sharp eye over hard calculation.
Find exactly HOW the first pair is connected, then build the same connection on the other side.
| Relationship type | Example |
|---|---|
| Part to whole | Page : Book :: Wheel : Car |
| Worker to tool | Carpenter : Saw :: Barber : Scissors |
| Capital to country | Delhi : India :: Tokyo : Japan |
| Cause to effect | Fire : Smoke :: Rain : Flood |
| Number relationship | 6 : 36 :: 8 : 64 (square) |
Three of the four items share ONE property. Ask what most of them have in common before you decide.
Rule for a fair question: only ONE property should ever pick out a single odd one. If two different rules (like "even" and "not a multiple of 3") both point at different items, the question is broken — a well-made set always has just one defensible answer.
Every code has one hidden rule. Write out the alphabet with numbers under it, and the rule becomes visible.
🔑 Two common code types
Shift code: every letter moves forward or back by the same amount. CAT + 1 each → DBU.
Reverse-alphabet code: A ↔ Z, B ↔ Y, C ↔ X … each letter swaps with its "opposite" from the other end. CAT → XZG.
🪜 The reverse-alphabet shortcut
A letter's position from the start plus its position from the end always adds up to 27. So D (4th) pairs with the 23rd letter, which is W.
Write the gaps underneath. If they are not equal, look for a growing pattern, a square/cube rule, or two operations alternating.
12 IMO-style questions. Use rough paper for the codes and series! 🍀