MathStatistics
posted by Anonymous .
I have a couple of questions that need reviewI've answered them, but I'm not sure if I'm correct.
1.)Suppose you interview 10 randomly selected workers and ask how many miles they commute to work. You'll compute the sample mean commute distance. Now imagine repeating the survey many, many times, each time recording a different sample mean commute distance. In the long run, a histogram of these sample means represents:
a) the bias, if any, which is present in the sampling method
b)the true population average commute distance
c)simple random sample
d)the sampling distribution of the sample mean
I chose choice "d" but I was torn between that and choice "b"
2)The average age of residents in a large residential retirement community is 69 years with standard deviation 5.8 years. A simple random sample of 100 residents is to be selected, and the sample mean age of these residents is to be computed.
We know the random variable has approximately a normal distribution because of
Choose one answer.
a. the central limit theorem.
b. the law of large numbers.
c. the 68–95–99.7 rule.
d. the population we're sampling from has a Normal distribution.
I chose choice "a"

Looks OK!