Two pain relief drugs are being considered. Drug I has shown in the past to have a standard deviation sigma 1 =4 minutes. A random sample of 8 doses of the first drug showed that the average amount of time required before the was absorbed into the bloodstream was x 1 =24 minutes. For the second drug, the historical data indicated a standard deviation sigma 2 =3.9 minutes. A random sample of 10 doses showed the average time required for absorption was overline x 2 =29 minutes . Assume the absorption times follow a normal distribution. a. Should you use the Z-Distribution or T- Dstribution in determining a confidence interval in this problem Explain. b. Find a 95% confidence interval for the difference in average absorption time for the two drugs   c Does it appear that one drug is absorbed faster than the other (at the 95% level)? Explain

The heart rate of 20 patients in the ICU have a mean of 95.3 beats per minute and a standard deviation of 19.6 beats per minute. Are heart rates from the ICU patients unusual given a normal heart rate has a mean of 72 beats per minute? What is the t-stastic?

You have obtained the number of years of education from one random sample of 38 police officers from City A and the number of years of education from a second random sample of 30 police officers from City B. The average years of education for the sample from City A is 15 years with a standard deviation of 2 years. The average years of education for the sample from City B is 14 years with a standard deviation of 2.5 years. Is there a statistically significant difference between the education levels of police officers in City A and City B?What is the appropriate test for this case? 2 sample z-testChi-square test     2-sample t-test2 sample paired t-test Carry out the test. The test statistic =   (round answer to two decimal places.)and the p-value is   (round answer to 2 decimal places)There     sufficient evidence at the 5% level to conclude that the education levels of police officers in City A and City B is significantly different.

What raw score for age corresponds to a z- score of +4.50, given a mean of 12.0 years and a standard deviation of 4.0 years?

Researchers interested in determining the relative effectiveness of two different drug treatments on people with a chronic illness established two independent test groups. The first group consisted of 12 people with the illness, and the second group consisted of 14 people with the illness. The first group received treatment 1 and had a mean time until remission of 166 days with a standard deviation of 8 days. The second group received treatment 2 and had a mean time until remission of 163 days with a standard deviation of 9 days. Assume that the populations of times until remission for each of the two treatments are normally distributed with equal variance. Construct a 90% confidence interval for the difference −μ1μ2 between the mean number of days before remission after treatment 1 ( μ1 ) and the mean number of days before remission after treatment 2 ( μ2 ). Then find the lower limit and upper limit of the 90% confidence interval. Carry your intermediate…

A psychologist is studying smokers self images, which she measures by the self image (SI) score from a personality inventory. For adults in the U.S., the mean SI score from this inventory is about 140. The psychologist gathers a random sample of 17 SI scores of smokers and finds that their mean is 164 and their standard deviation is 38. Assume that the population of SI scores of smokers is normally distributed with mean μ. Based on the sample, can the psychologist conclude that μ is different from 140? Use the 0.05 level of significance. Perform a two-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places and round your answers as specified in the table.

A psychologist is studying smokers' self-images, which she measures by the self-image (SI) score from a personality inventory. For adults in the U.S., the mean SI score from this inventory is about 150.  The psychologist gathers a random sample of 16 SI scores of smokers and finds that their mean is 130 and their standard deviation is 31. Assume that the population of SI scores of smokers is normally distributed with mean μ. Based on the sample, can the psychologist conclude that μ is different from 150? Use the 0.05 level of significance. Perform a two-tailed test. Then fill in the table attached. Carry your intermediate computations to at least three decimal places and round your answers as specified in the table.