Lube-Tech Is a Major Chain Whose Primary Business Is Performing

question 84

True/False

Lube-Tech is a major chain whose primary business is performing lube and oil changes for passenger vehicles. The national operations manager has stated in an industry newsletter that the mean number of miles between oil changes for all passenger cars exceeds 4,200 miles. To test this, an industry group has selected a random sample of 100 vehicles that have come into a lube shop and determined the number of miles since the last oil change and lube. The sample mean was 4,278 and the sample standard deviation was 780 miles. Based on this information, the test statistic is approximately t = 1.000.

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Definitions:

Observations Rank

The process of assigning ordinal ranks to data points based on their value or position relative to other points in the dataset.

Nonparametric Methods

Statistical methods that are not based on parameterized families of probability distributions, often used with data that doesn't meet the assumptions of parametric tests.

Any Distribution

A general term that refers to the entire range of distributions a variable can follow, not limited to normal, binomial, etc.

Normal Distribution

A bell-shaped frequency distribution curve where most of the occurrences take place around the central peak and the probabilities of extreme occurrences taper off equally on both sides.