Breaking Strength of Steel Cable The average breaking strength of a certain brand of steel cable is 2000 pounds, with a standard deviation of 100 pounds. A sample of 20 cables is selected and tested. Find the sample mean that will cut off the upper 80% of all samples of size 20 taken from the population. Assume the variable is normally distributed. Round intermediate z-value calculations to 2 decimal places and round the final answer to at least 2 decimal places. The sample mean that will cut off the upper 80% of all samples of size 20 is pounds .
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80 + \frac{1 - 0.80}{2} = 0.80 + 0.10 = 0.90\] Show more…
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Breaking Strength of Steel Cable The average breaking strength of a certain brand of steel cable is 2000 pounds, with a standard deviation of 100 pounds. A sample of 20 cables is selected and tested. Find the sample mean that will cut off the upper $95 \%$ of all samples of size 20 taken from the population. Assume the variable is normally distributed.
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The average breaking strength of a certain brand of steel cable is 2000 pounds, with a standard deviation of 100 pounds. A sample of 20 cables is selected and tested. Find the sample mean that will cut off the upper 95% of all samples of size 20 taken from the population. Assume the variable is normally distributed.
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