1. Suppose a sample of n = 50 items is drawn from a population of manufactured products and the weight, X, of each item is recorded. Prior experience has shown that the weight has a probabilitydistribution with mean= 6 ounces and standard deviation= 2.5 ounces. Which of the following is true about the samplingdistribution of the sample mean if a sample of size 15 is selected?
a) The mean of the sampling distributionis 6 ounces.
b) The standard deviationof the sampling distribution is 2.5 ounces.
c) The shape of the sample distribution is approximately normal.
d) All of the above are correct.
2. 10. Major league baseball salaries averaged $1.5 million with a standard deviation of $0.8 million in 1994. Suppose a sample of 100 major league players was taken. Find the approximate probability that the average salary of the 100 players exceeded $1 million.
(1) A is true because the mean of the sampling distribution (of all samples) tends to the population mean as n increases.
B is not true. The standard deviation of the sample is not necessarily equal to the …
Both questions solved methodically.