A researcher is interested in finding a 95% confidence interval for the mean number minutes students are concentrating on their professor during a one hour statistics lecture. The study included 142 students who averaged 37.2 minutes concentrating on their professor during the hour lecture. The standard deviation was 11.9 minutes. Round answers to 3 decimal places where possible. a. To compute the confidence interval use a ? v distribution. b. With 95% confidence the population mean minutes of concentration is between and minutes. c. If many groups of 142 randomly selected members are studied, then a different confidence interval would be produced from each group. About percent of these confidence intervals will contain the true population mean minutes of concentration and about percent will not contain the true population mean minutes of concentration. Submit Question 52°F Cloudy 99+

In a survey, 373 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped with a mean of $36.85 and standard deviation of $19.05. Estimate how much a typical parent would spend on their child's birthday gift (use a z-interval at a 80% confidence level). Give your answers to 2 decimal places. Express your answer in the format of E. $ + $

a. interpret the corresponding 95% confidence intervals for both Birth weight and Age.  b. What is the predicted average SBP of an infant born with birth weight 8lbs (128oz) measured at 3 days old? c. Calculate the Pearson correlation between Age and Birth weight, and test if this correlation is significant at the 0.05 level. Does this answer surprise you, why or why not?

Answer A B C

Tina catches a 14-pound bass.  She does not know the population mean or standard deviation.  So she takes a sample of five friends and they say the last bass they caught was 9, 12, 13, 10, and 10 pounds.  Find the t and calculate a 95% (α = .05) confidence interval.

In a survey, 21 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped with a mean of $30 and standard deviation of $14. Construct a confidence interval at a 80% confidence level.Give your answers to one decimal place. ______   ±  _______

Please help with 6 a-b

The mayor is interested in finding a 95% confidence interval for the mean number of pounds of trash per person per week that is generated in the city. The study included 249 residents whose mean number of pounds of trash generated per person per week was 34.8 pounds and the standard deviation was 7.2 pounds. Round answers to 3 decimal places where possible. b. With 95% confidence the population mean number of pounds per person per week is between   ?  and   ?  pounds. c. If many groups of 249 randomly selected members are studied, then a different confidence interval would be produced from each group. About        ?  percent of these confidence intervals will contain the true population mean number of pounds of trash generated per person per week and about    ?   percent will not contain the true population mean number of pounds of trash generated per person per week.

The mayor is interested in finding a 99% confidence interval for the mean number of pounds of trash per person per week that is generated in the city. The study included 236 residents whose mean number of pounds of trash generated per person per week was 33.6 pounds and the standard deviation was 8.7 pounds. Round answers to 3 decimal places where possible. b. With 99% confidence the population mean number of pounds per person per week is between    ?  and  ?  pounds. c. If many groups of 236 randomly selected members are studied, then a different confidence interval would be produced from each group. About        ?    percent of these confidence intervals will contain the true population mean number of pounds of trash generated per person per week and about    ?    percent will not contain the true population mean number of pounds of trash generated per person per week.