An auto maker estimates that the mean gas mileage of its sports utility vehicle is at least 20 miles per gallon. A random sample
of 36 such vehicles had a mean of 18 miles per gallon and a standard deviation of 5 miles per gallon. At α = .01 can you reject the auto maker's claim?
The set of integers consists of zero ( ), the positive natural numbers ( , , , …), also called whole numbers or counting numbers , and their additive inverses (the negative integers , i.e., −1, −2, −3, …). The set of integers is often denoted by a boldface Z ( ) or blackboard bold mathbb (Unicode U+2124 ℤ) standing for the German word Zahlen ( , numbers ).