Question

1. The effectiveness of a blood-pressure drug is being investigated. An experimenter finds that, on average, the reduction in systolic blood pressure is 38.9 for a sample of size 339 and standard deviation 13.4.

Estimate how much the drug will lower a typical patient's systolic blood pressure (using a 80% confidence level).

Enter your answer as a tri-linear inequality accurate to one decimal place (because the sample statistics are reported accurate to one decimal place).

_____________< μ <________________

2. You must estimate the mean temperature (in degrees Fahrenheit) with the following sample temperatures:

38.1

45.5

51.4

42

29.8

42.4

38.1

41.1

30.8

28.9

46.5

32.5

Find the 99% 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).

99% C.I. = ____________________

Answer should be obtained without any preliminary rounding.

Answer 1

1)

The statistic software output for this problem is:

38.0 <   < 39.8

2)

99% CI is : (32.44 , 45.40)