Answer Happy

Q1. [2] The confidence interval for a population mean is given as (17.44,17.78). Compute the margin of error, E. Q2. [4] A chemist examines 14 sedimentary samples for magnesium concentration. The mean magnesium concentration for the sample data is 0.030cc/ cubic meter with a sample standard deviation of 0.0771. Determine the 90% confidence interval for the population mean magnesium concentration. Assume the population is approximately normal. Q3. [4] A scientist claims that 6% of viruses are airborne. Construct the 95% confidence interval for the population proportion when we take a sample of size 592 . Q4. [2+3+3] The director of research and development is testing a new drug. She wants to know if there is evidence at the 0.1 level that the drug stays in the system for more than 364 minutes. For a sample of 82 patients, the mean time the drug stayed in the system was 368 minutes. Assume the population standard deviation is 21 . (a) Is it a left tailed or a right tailed or a two tailed test? (b) Compute the test statistic. (c) Make the decision to reject or fail to reject the null hypothesis.