Posted: February 16th, 2017

The manufacturer claims that the “average” Rockwell hardness index for this type of steel exceeds 60.Determine if there is sufficient evidence to support the manufacturer’s claim

Problem set 8, Question 11 [WSRT] note: data values have been sorted below to help calculations. The Rockwell hardness index for steel is determined by pressing a diamond point into the steel andmeasuring the depth of the penetration. Below are the Rockwell hardness indices for a random sample of25 specimens of a particular type of steel.46 51 54 56 56 57 59 59 60 60 65 65 66 67 68 69 69 70 71 72 73 74 74 76 79The manufacturer claims that the “average” Rockwell hardness index for this type of steel exceeds 60.Determine if there is sufficient evidence to support the manufacturer’s claim. (? = .01)