Question

A random selection of volunteers at a research institute have been exposed to a typical cold virus. After they started to have cold symptoms, 10 of them were given multivitamin tablets daily which contain 1 gram of vitamin C and various other vitamins and minerals. The remaining 10 volunteers were given tablets only containing 4 grams of vitamin C. For each individual, the length of time taken to recover from cold is recorded. At the end of the experiment the following data are obtained: Days to recover from cold Treated with multivitamin 2, 3.6, 2.7, 4.3,6.6,6.8,6.6, 2.7, 5.4,9.1 Treated with Vitamin C4.7,62,4.5, 3.3, 3.7, 3.4,4.6, 5.8,3.2.6.3 Send dats to Exce It is known that the population standard deviation of recovery time from cold is 1.8 days when treated with multivitamin, and the population standard deviation of recovery time from cold is 1.5 days when treated with vitamin C tablets. It is also known that both populations are approximately normally distributed. The researchers claim that the mean recovery time, , of the patients treated with multivitamin is less than or equal to the mean recovery time ju, of the patients who are treated with vitamin C tablets. At the 0.1 level of significance, is there enough evidence to reject this claim? Perform a one-tailed test. Then fill in the table below. Carry your intermediate computations to at least three decimal places and round your answers as specified in the table. (If necessary, consult a list of formulas.) EQuestion 2 of 5 (6 points) talbie Deiow Carry your intermediate computations to at least three decimal places and round your answers as specified in the table. H The null hypothesis: 0 X The alternative hypothesis: (Choose one) The type of test statistic: ? The value of the test statistic: (Round to at least three decimal places.) The p-value: (Round to at least three decimal places.) Can we reject the researchers' claim that the mean recovery time when treated with multivitamin is less than or equal to the mean recovery time when treated with vitamin C only? O Yes O No X

Answer 1

43 45. Hypotyesest Ha lestJ Z est standard nor ma Te ststatis trc 2 te st - , - 45 7- 4.3 D. SS3 /8D }.SO 0 P valne at z -0553 P/27 0.553) PI2 0.553) -t0 - 0. 71 =L0. 290 P va lne we Pauled to reJe ct Ho P value o.10, We can a oesect fhe researcherr c lam.