Bear Inc.'s share price closed at $100, $105, $56, $30, $2 over five successive weeks. The weekly standard deviation of the stock price calculated from this sample is

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Quizplus · Accepted Answer

The standard deviation of the stock prices can be calculated using the formula for standard deviation for a sample. First, find the mean (average) of the prices: (100 + 105 + 56 + 30 + 2) / 5 = 293 / 5 = 58.6. Then, calculate the variance by finding the squared differences from the mean, summing them, and dividing by the number of observations minus one (n-1 for a sample): [(100-58.6)^2 + (105-58.6)^2 + (56-58.6)^2 + (30-58.6)^2 + (2-58.6)^2] / (5-1) = 7880.8 / 4 = 1970.2. The standard deviation is the square root of the variance, which is √1970.2 ≈ 44.43.

Bear Inc'S Share Price Closed at $100, $105, $56, $30, $2