John Kleman is the host of KXYZ Radio 55 AM drive-time news in Denver. During his morning program, John asks listeners to call in and discuss current local and national news. This morning, John was concerned with the number of hours children under 12 years of age watch TV per day. The last five callers reported that their children watched the following number of hours of TV last night.
Would it be reasonable to develop a confidence interval from these data to show the mean number of hours of TV watched? If yes, construct an appropriate confidence interval and interpret the result. If no, why would a confidence interval not be appropriate?
Consider all of the coins (pennies, nickels, quarters, etc.) in your pocket or purse as a population. Make a frequency table beginning with the current year and counting backward to record the ages (in years) of the coins. For example, if the current year is 2017, then a coin with 2015 stamped on it is 2 years old.
a. Draw a histogram or other graph showing the population Randomly select five coins and record the mean age of the sampled coins.
Repeat this sampling process 20 times. Now draw a histogram or other graph showing the of the sample means. c. Compare the shapes of the two histograms.
Consider the digits in the phone numbers on a randomly selected page of your local phone book a population. Make a frequency table of the final digit of 30 randomly selected phone numbers. For example, if a phone number is 555-9704, record a 4.
a. Draw a histogram or other graph of this population Using the uniform compute the population mean and the population standard deviation.
b. Also record the sample mean of the final four digits (9704 would lead to a mean of 5). Now draw a histogram or other graph showing the of the sample means.
c. Compare the shapes of the two histograms.
For the year 2017, Fred Friendly completed a total of 80 returns. He developed the following table summarizing the relationship between number of dependents and whether or not the client received a refund.
a. What is the name given to this table?
b. What is the probability of selecting a client who received a refund?
c. What is the probability of selecting a client who received a refund or had one dependent?
d. Given that the client received a refund, what is the probability he or she had one dependent?
e. What is the probability of selecting a client who did not receive a refund and had one dependent?