The standard deviation of the wages of 400 textile workers is $ 12.8. Another sample of 600 textile workers gives the standard deviation at $ 15.7. Find out if the standard deviation of the first...

Extracted text: The standard deviation of the wages of 400 textile workers is $ 12.8. Another sample of 600 textile workers gives the standard deviation at $ 15.7. Find out if the standard deviation of the first sample significantly differs from the combined deviation of the two samples which is $. 14.