What is the variance if the data set is {5, 10, 15, 20, 25}?
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What is the equation of an ellipse centered at (h,k), with a major axis of length 2a and a minor axis of length 2b?
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Math question: What is the sum of cubes a^3 + b^3 if a, b, and c are positive integers satisfying Fermat's theorem for n=3, and c is the hypotenuse of a right-angled triangle?