sudhanshu kumar

An automobile manufacturer claims that a particular model gets 28 miles to the gallon. The Environmental Pollution Agency, using a sample of 49 automobiles of this model, finds the sample mean to be 26.8 miles per gallon. From previous studies, the popula...

Hinton Press hypothesizes that the average life of its largest web press is 14,500 hours. They know that the standard deviation of press life is 2,100 hours. From a sample of 25 presses, the company finds a sample mean of 13000 hours. At a 0.01 significan...