Question

The diameters of a random sample of 20 products made by a certain machine during one month showed a mean of 0.93 inch and a sample standard deviation of 0.05 inch. Assume the population is normally distributed, find a 95% confidence intervals for the mean diameter of all the products.

Select one:

a. 0.9107 to 0.9493 inch

b. 0.9066 to 0.9534 inch

c. 0.9081 to 0.9519 inch

d. 0.9248 to 0.9352 inch

Answer #1

The diameters of a random sample of 20 products made by a
certain machine during one month showed a mean of 0.93 inch and a
sample standard deviation of 0.05 inch. Assume the population is
normally distributed, find a 95% confidence intervals for the mean
diameter of all the products.
Select one:
a. 0.9066 to 0.9534 inch
b. 0.9081 to 0.9519 inch
c. 0.9248 to 0.9352 inch
d. 0.9107 to 0.9493 inch
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