Question

In
a random sample of 198 engine crankshaft bearings 33% have a
surface finish that is rougher than the specifications allow. Find
a 90% confidence interval for the proportion of bearins in the
population that exceeds the roughness specifications.

Answer #1

given data are:-

sample size (n) = 198

sample proportion () = 0.33

*z critical value
for 90% confidence level, both tailed test be:-*

**the 90%
confidence interval for the proportion of bearins in the population
that exceeds the roughness specifications is:-**

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