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Every positive integer can be broken down into powers of two. Can you spot the shortcut to a special kind of sum?
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?
Sometimes, we can rearrange the numbers in a grid so that every row and column has the same sum. Instead, could we make this sum by replacing numbers with 0s?
In a tracing puzzle, you can’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.
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