Questions:

0 Question 1 v B 0/ 3 pts '0 A study of North York University students showed the mean age of all students in the first year of university to be 20.6 years old with a standard deviation of 0.9 years. A randomly selected subgroup of these first year students also averaged 20.7 years in age with a standard devaition 0.89 years. a) Are the numbers 20.6 and 0.9 statistics or parameters? Explain. O The numbers are statistics because the numbers were calculated for all North York University's first year students. 0 The numbers are statistics because the numbers were calculated for a sample of North York University students and are therefore estimates. 0 The numbers are parameters because the numbers were calculated for a sample of North York University students and are therefore estimates. 0 The numbers are parameters because they were calculated for all North York University's first year students. b) Are the numbers 20.7 and 0.89 statistics or parameters? Explain. O The numbers are parameters because they were calculated for a sample of North York University students and are therefore estimates. 0 The numbers are parameters because they were calculated for all North York University's first year students. 0 The numbers are statistics because the numbers were calculated for a sample of North York University students and are therefore estimates. 0 The numbers are statistics because the numbers were calculated for all North York University's first year students. c) Select any correct pair of labels and values below: Op = 20.7 and a = 0.9 Op, 2 20.6 and a = 0.89 03': = 20.7 and 3 = 0.9 05 = 20.6 and s = 0.9 Oi = 20.6 and a = 0.9 Oi = 20.7 and a = 0.9 O\" = 20.6 and s = 0.89 O\" = 20.7 and s = 0.89 0 Question 2 v Express the confidence interval 611.5 :|: 135.6 in the form of a trilinear inequality. C]

Length of a confidence interval. Which confidence interval would be shorter, a confidence interval computed using a confidence level of 95% or a confidence interval computed using a confidence level of 99%. Assume the sample sizes are the same in each case and the only difference between the confidence intervals is the confidence level. 0 The 95% confidence interval would be shorter since the 2:6 or tc values are smaller when the confidence level is 95% leading to smaller margin of error. 0 The 99% confidence interval would be shorter since the zc or tc values are smaller when the confidence level is 95% leading to smaller margin of error. 801' \f0 Question 6 v For a confidence level of 95%, find the critical .3 value. Round to at least 2 decimal places. 0 Question 7 ' B 0/2 pts ' You measure 23 textbooks' weights, and find they have a mean weight of 49 ounces. Assume the population is normally distributed with a standard deviation of 12.6 ounces. Based on this, construct a 90% confidence interval for the true population mean textbook weight. Give your answers correct to at least two decimal places. Lower Limit = I:] Upper Limit = You measure 20 watermelons' weights, and find they have a mean weight of 65 ounces. Assume the population standard deviation is 7.2 ounces. Based on this, construct a 95% confidence interval for the true population mean watermelon weight. Give your answers as i :|: ME, to two decimal places C] . Dances