Mean is calculated by adding up all the values in a sample, then dividing by the total number of values. Calculate the mean of the sample: 10, 20, 30, 40, and 50.
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What is the equation of a parabola with vertex at (2, 5) that opens downwards?
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Math question: What is the scalar product of vector A = (3, -2) and vector B = (-4, 5)?