A pressure pipeline manufacturer has performed wall thicknes

A pressure pipeline manufacturer has performed wall thickness measurements for many years an knows that the true variance of the wall thickness of a pipe is 0.500 mm^2. If the variance of a sample is 1.02 mm^2, find the percent probability that this sample variance results from only random events. Assume a sample size of 16.

Solution

So, we have to test H0 : Population variance = 0.5 ag. Population variance not equals 0.5..

Test statistic =(n-1) [ sample variance / population variacne ]
   = (16 -1) [ 1.02 / 0.5 ] = 30.6.....

So, probability that this sample variance results from only random events = 0.9801346...or 98% (approx)