The inequality between arithmetic and geometric means allows us to find bounds for sums and products. What can't the four ages sum up to?
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Different bulb combinations produce different amounts of light. Which circuit will shine brighter?
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In this jigsaw map puzzle, the clues determine the locations of three of the pieces. Where can we place the fourth piece?
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To calculate the probability of an event, we count the number of ways the event could occur. Who is more likely to win?
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This cryptogram is the cat's MEOW; will it make you say WOW?
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One arrangement of the instructions makes X contain the square of the sum of A and B. What about the other arrangement?
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This teacher wrote a test question with more solutions than she wanted. How many fewer solutions are there when she changes a constraint?
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