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Probability

Standard deviation of daily profit from units sold

variancestandard-deviationlinear-transformation

A stall's daily profit in dollars is

P=8 X−100,P = 8\,X - 100,

where XX is the number of units sold that day, and 100100 is the fixed daily cost. The number of units sold has variance 2525 (so its standard deviation is 55).

What is the standard deviation of the daily profit?

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