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What looks like a geometry problem at first might turn out to be one in number theory. How many times will these lines intersect at a circle?

The current in this river is the fastest in the center. Which path will get the ferry across the river in the least time?

Toggle Tags puzzles are solved with logic. Given a mix of true and false information, how many solutions are there?

When we connect some of the corners of these squares, a quadrilateral is formed. Can you find its area?

Every positive integer can be broken down into powers of two. Can you spot the shortcut to a special kind of sum?

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?

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?

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