The fuel? consumption, in miles per? gallon, of all cars of a particular model has a mean of 28 and a standard deviation of 3.The population distribution can be assumed to be normal. A random sample of these cars is taken.
Find the probability that the sample mean fuel consumption will be fewer than 27 miles per gallon if samples of 1?, 4 and 9 are taken.
What is the probability for a sample of 1 observation