The angles in these triangles are related to one another. Can you find the measure of the yellow angle?
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El the Elephant wants to lift his five friends. Will this pulley suffice?
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Counting elements of the union of two sets is a bit more complicated than simply adding the elements of both. How many integers aren't divisible by 3 or 11?
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Smaller and smaller squares fill in the area around this square’s diagonal. What fraction of the large square’s area is shaded?
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Some of these Londoners are humans, and some are werewolves. Look for contradicting statements to find who's telling the truth and who isn't.
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You can get zero by changing some of the plus signs. Which operation must come first?
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Jeremiah wants to use every mode of transportation while sight-seeing. Where should he begin?
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