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PRIZ Riddles

Put your engineering intuition to work.

Short, sharp challenges designed to make you pause, reason, and see the problem differently.

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Riddle of the week New

Logic • Easy

Three switches. One trip.

A simple room, three identical switches, and one chance to observe. Can you extract enough information?

Every problem rewards a different way of thinking.

Riddle #01 • Logic 3 min Easy

Three switches. One trip.

A simple room, three identical switches, and one chance to observe. Can you extract enough information?

Riddle #02 • Systems thinking 5 min Hard

The factory bottleneck

A line is slow, every station looks busy, and adding people does not help. Where is the constraint?

Riddle #03 • Root cause 2 min Easy

The mysteriously wet floor

The floor is wet again. The leak looks obvious. Is it the cause, or only the symptom?

Riddle #04 • Creative thinking 4 min Medium

Make it lighter, not weaker: a long engineering contradiction in one sentence

The part must lose weight without losing strength, and every obvious cut seems to trade one for the other. How do you resolve the contradiction instead of compromising?

More than a brain teaser.

Practice the habits behind better problem solving.

Each explanation connects the answer to a practical thinking principle you can use on real engineering challenges.

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