The weight of adobe bricks for construction is normally distributed with a mean of 3 pounds and a standard deviation of 0.25 pound. Assume that the weights of the bricks are independent and that a random sample of 25 bricks is chosen. (a) What is the probability that the mean weight of the sample is less than 3.05 pounds? 0.1586 Round your answer to four decimal places (e.g. 98.7654). (b) What value will the mean weight exceed with probability 0.99? 2.88 Round your answer to two decimal places (e.g. 98.76).
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The standard error is given by the formula: Standard Error (SE) = \frac{Standard Deviation}{\sqrt{Sample Size}} = \frac{0.25}{\sqrt{25}} = \frac{0.25}{5} = 0.05 (a) We want to find the probability that the sample mean is less than 3.05 pounds. To do this, we Show more…
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