# Question: Manufacturing specifications are often based on the results of samples

Manufacturing specifications are often based on the results of samples taken from satisfactory pilot runs. The following data resulted from just such a situation, in which eight pilot batches were completed and sampled. The resulting particle sizes are in angstroms (where 1 Å = 10_8 cm):

3923 3807 3786 3710 4010 4230 4226 4133

a. Find the sample mean.

b. Find the sample standard deviation.

c. Assuming that particle size has an approximately normal distribution, determine the manufacturing specification that bounds 95% of the particle sizes (that is, find the 95% interval, ± 2s).

3923 3807 3786 3710 4010 4230 4226 4133

a. Find the sample mean.

b. Find the sample standard deviation.

c. Assuming that particle size has an approximately normal distribution, determine the manufacturing specification that bounds 95% of the particle sizes (that is, find the 95% interval, ± 2s).

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