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Successfully pulling off the tablecloth trick can require a lot of trial and error, spilt drinks, and broken glass. Can you master it a smarter way?

In a tracing puzzle, you canâ€™t lift your writing tool or go over a segment twice. This triangle is impossible, but is tracing it impossible, too?

Similar triangles can often hide in unexpected places. Could they help with this challenge?

In multi-level mobiles, weights on one level can affect another. Can you salvage this mobile, or is it unavoidably unbalanced?

With some reasoning, you can find a shortcut for the final digit of this multiplication problem.

Finding the probability of a single die roll is pretty simple. But what happens when more than one die is involved?

This cryptogram has multiple solutions, but that doesn't mean every digit changes in every solution. Which digits never change?

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