Question

1) You measure 28 turtles' weights, and find they have a mean weight of 75 ounces. Assume the population standard deviation is 14.2 ounces. Based on this, construct a 99% confidence interval for the true population mean turtle weight. Give your answers as decimals, to two places ± ± ounces

2) Assume that a sample is used to estimate a population mean μ μ . Find the margin of error M.E. that corresponds to a sample of size 7 with a mean of 72.7 and a standard deviation of 17.7 at a confidence level of 80%. Report ME accurate to one decimal place because the sample statistics are presented with this accuracy. M.E. = Incorrect Answer should be obtained without any preliminary rounding. However, the critical value may be rounded to 3 decimal places.

3) You must estimate the mean temperature (in degrees Fahrenheit) with the following sample temperatures: 51.6 62.8 64.6 60.2 45.7 50 69.4 Find the 90% confidence interval. Enter your answer as an open-interval (i.e., parentheses) accurate to two decimal places (because the sample data are reported accurate to one decimal place). 90% C.I. = 52.373,63.227Incorrect Answer should be obtained without any preliminary rounding

4) SAT scores are distributed with a mean of 1,500 and a standard deviation of 300. You are interested in estimating the average SAT score of first year students at your college. If you would like to limit the margin of error of your 95% confidence interval to 25 points, how many students should you sample? Make sure to give a whole number answer

. 5) If n=11, ¯ x x ¯ (x-bar)=48, and s=10, find the margin of error at a 98% confidence level Give your answer to two decimal places. 6) In a survey, 22 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped with a mean of $42 and standard deviation of $8. Construct a confidence interval at a 90% confidence level. Give your answers to one decimal place. Incorrect ± ± Incorrect Interpret your confidence interval in the context of this problem.

Answer 1

According to the rules only first question will be answered.