ATC is having nine machines which produces these slip-ring bearing. James, a quality
inspector randomly selected Machine #3 and Machine #7. A sample of 200 slip-ring
bearings selected from each machine production and there diameter measured in
centimetres.
According to the given specification of this type of bearing the acceptable diameters
ranges between 4.95 and 5.05 centimetres i.e. any bearing below 4.95cm or above
5.05cm is considered defective. Assume data is normally distributed.

A) is it matched or independent
B)Can James conclude that Machine #7 has lower defective rate than Machine #3?( how to write the null hypothesis and alternative)..