Question

Doctors are comparing the efficacy of two painkillers. They randomly assign one of the two painkillers to their patients and measure time to relief for each individual. The group assigned painkiller 1 has 41 people in it. The group assigned painkiller 2 has 61 people in it. For group 1, the mean time to relief is 10 minutes, and the sample variance is 2 minutes. For group 2, the mean to time to relief is 9.5 minutes, and the sample variance is 3.5 minutes.

A) Construct a 95% confidence interval for the difference in average time to relief for the two painkillers.

B) Based on the confidence interval in part (a), the doctors conclude that the two painkillers are quite similar in their average time to relief. However, they noticed that painkiller 2 had a higher sample variance than painkiller 1. Perform a hypothesis test to determine if the variance for painkiller 2 is significantly higher than for painkiller 1. Test at the α = .05 level. (You may make any necessary assumptions to make the hypothesis test feasible.)

Also, if you're going to write the answer please write in a way where it's highly easy to read your handwriting. I don't mean to be rude, but I've had answers from chegg before that were almost worthless because I could only half read the handwriting. So if you're going to write please make sure your writing is very readable. Thank you.

Answer #1

**Solution:**

An investigation is undertaken to
examine the average times to relief from headache pain under two
entirely different treatments: Medication vs. Relaxation. Patients
suffering from chronic headaches are enrolled in a study and
randomly assigned to one of the two treatment groups. Patients are
instructed to either take the assigned medication or to perform the
relaxation exercises at the onset of their next headache. They are
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Do a t-test of sample means differences assuming unequal
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minutes Variance = 29 minutes Sample size = 41 flights Sample 2
flight times Charlotte To Dallas with Airbus 320 Mean time 201
minutes Variance = 39 minutes Sample size = 67 flights

A research study was conducted to examine the efficacy of
studying in groups. Students were randomly assigned to one of two
groups: a single person group (individual studying), a group that
had three study partners. After four weeks of studying, the
students were given an exam. The raw scores on the exam are below.
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Group 1 Group 2
78 82
87 79
76 82
65 83
92 81
78 90
77 89
88 79
85 83...

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To test their belief, the consumer advocacy group took a random
sample of 45 hospital patients who were currently experiencing a
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A social psychologist studying mass communication randomly
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seven were instructed to get their news for a month only from
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These were the results of the study. TV...

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method gives an average mean time of 20.5 minutes with variance of
3 minutes. A random sample of 50 for the second method gives an
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Determine the 95% confidence interval for the difference
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At alpha =0.05...

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Cindy has two groups. She randomly assigns subjects to her two
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She predicts that the sad group will be more persuaded than the
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Tell me the if the hypothesis stated is...

10 subjects in a study were randomly assigned into two
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A survey asked a group of medical doctors how many children they
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Number of Children
0
1
2
3
4
6
Number of Doctors
18
14
24
14
6
3
(a) Calculate the sample mean for the number of children the
doctors had fathered. (Give your answer correct to two decimal
places.)
(b) Calculate the variance for the number of children the doctors
had fathered using the short-cut formula...

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