The Chrysler Corporation is pushing its new Dodge Ram pickup trucks heavily through advertising. One of critisisms of previous models of the Ram pickup was that they're noisy while driving at highway speeds. Dan Richter is the marketing manager at Chrysler and desires to claim that this year's model is quieter than the previous model. He is adamant that research supports that claim before he will go forward with the claim. Chrysler had measured sound level of last year's model and the average sound level was 54 decibels at 55 miles per hour with the standard deviation of 5.8 decibels. The standard deviation is thought to be consistent for overall population of Ram trucks. A sample of 36 new models yielded average sound level of 52 decibels at 60 miles per hour.
Conduct an Hypothesis Test that would give evidence for Chrysler to support the statement that new model is quieter than last year's model.
Determine the Null and Alternate Hypotheses
Use a confidence level of 95%