The lifetime of Brand A tires are distributed with mean 45,000 miles and standard deviation 4900...

The lifetime of Brand A tires are distributed with mean 45,000 miles and standard deviation 4900 miles, while Brand B tiees last for only 36,000 miles on the average(mean) with standard deviation of 2010 miles. Niccoles Brand A tires lasted 37,000 miles and Yvettes Brand B tires lasted 35,000 miles. Relatively speaking, within their own brands, which driver fot the better wear?

Solutions

Expert Solution

Result:

z = (x-µ)/σ

Z score for Niccoles, z =(37000-45000)/4900 = -1.63

Z score for Yvettes, z =(35000-36000)/2010 = -0.50

Yvettes z score is larger than Niccoles z score.

Within their own brands, Yvettes is the better wear than Niccoles.

orchestra answered 1 year ago

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