Perform a one-sample z-test for a population mean using the P-value approach. Be sure to state the hypotheses and the significance level, to compute the value of the test statistic, to obtain the P-value, and to state your conclusion. In the past, the mean running time for a certain type of flashlight battery has been 7 hours. The manufacturer has introduced a change in the production method which he hopes has increased the mean running time. The mean running time for a random sample of 40 light bulbs was 7.2 hours. Do the data provide sufficient evidence to conclude that the mean running time of all light bulbs, µ, has increased from the previous mean of 7 hours? Perform the appropriate hypothesis test using a significance level of 0.05. Assume that o = 0.5 hours. Ho :µ=7.2 hours H : µ>7.2 hours a= 0.05 z= 2.80 P-value =0.0026 Reject H, . At the 5% significance level, the data provide sufficient evidence to conclude that the mean running time of all light bulbs, u, has increased from the previous mean of 7,2 hours. H :µ=7 hours H : µ>7 hours a=0.05 O== 2.53 P-value = 0.0057 Reject H,. At the 5% significance level, the data provide sufficient evidence to conclude that the mean running time of all light bulbs, u, has increased from the previous mean of 7 hours. Ho : µ=7 hours H : µ>7 hours a= 0.05 O==2.80 P-value =0.0026 Reject Ho. At the 5% significance level, the data provide sufficient evidence to conclude that the mean running time of all light bulbs, u, has increased from the previous mean of 7 hours. Ho: H= 7.2 hours H : µ>7.2 hours a=0.05 Oz= 2.53 P-value = 0.0057 Reject H.. At the 5% significance level, the data provide sufficient evidence to conclude that the mean running time of all light bulbs, µ, has increased from the previous mean of 7.2 hours.

Using traditional methods it takes 99 hours to receive an advanced driving license. A new training technique using Computer Aided Instruction (CAI) has been proposed. A researcher used the technique on 190 students and observed that they had a mean of 100 hours. Assume the population variance is known to be 49. Is there evidence at the 0.05 level that the technique lengthens the training time?   Step 4 of 6 :  Find the P-value of the test statistic. Round your answer to four decimal places.

An article in the San Jose Mercury News stated that students in the California state universitysystem take 4.25 years, on average, to finish their undergraduate degrees. Suppose you believe that the mean time is longer. You conduct a survey of 64 students and obtain a sample mean of 4.5 with a sample standard deviation of 1.5. Do the data support your claim at the 1% level?

Reports on a student's ACT, SAT, or MCAT usually give the percentile as well as the actual score. The percentile is the cumulative proportion stated as a percentage: the percentage of all scores that were lower than this one. In 2019, the scores on the Mathematics portion of the SAT were close to Normal, with mean 528528 and standard deviation 117. Joseph scored 411.411. What was his percentile?

A developmental psychologist is interested in studying how long babies gaze at a photograph of a human face. To test this question, she shows a picture to a sample of six babies and records the length of their gaze in seconds. The data are as follows: 12, 17, 18, 20, 20, 29. Calculate the mean, median, mode, range, variance and standard deviation for the sample.

In a t-test for paired samples, the one value that compares, for each person, her or his two measurements is called the                                   .       Difference score     Deviation score     Standard deviation     Standard difference

Choose the appropriate statistical test. When computing, be sure to round each answer as indicated. A dentist wonders if depression affects ratings of tooth pain. In the general population, using a scale of 1-10 with higher values indicating more pain, the average pain rating for patients with toothaches is 6.8. A sample of 30 patients that show high levels of depression have an average pain rating of 7.1 (variance 0.8). What should the dentist determine? 1. Calculate the estimated standard error. (round to 3 decimals). [st.error] 2. What is thet-obtained? (round to 3 decimals). 3. What is the t-cv? (exact value) 4. What is your conclusion? Only type "Reject" or Retain"

A local convenience store in a large city closes each day at 10 P.M. The owner of the store is investigating whether mean sales will increase by at least $10 per day if the store remains open until 11 P.M. The owner asked the 41 members of a local civic group to estimate the amount of money they might spend during the extra hour. The sample mean was $11.50. The owner will conduct a one-sample tt-test for a population mean. Have the conditions for inference been met? A)nYes, all conditions have been met. B) No, the sample was not chosen using a random method. C) No, the sample size is greater than 10 percent of the population. D) No, the sample size is not large enough to assume normality of the sampling distribution. E) No, the distribution of the sample is not normal.

A local convenience store in a large city closes each day at 10 P.M. The owner of the store is investigating whether mean sales will increase by at least $10 per day if the store remains open until 11 P.M. The owner asked the 41 members of a local civic group to estimate the amount of money they might spend during the extra hour. The sample mean was $11.50. The owner will conduct a one-sample tt-test for a population mean. Have the conditions for inference been met?     Yes, all conditions have been met. A No, the sample was not chosen using a random method. B No, the sample size is greater than 10 percent of the population. C No, the sample size is not large enough to assume normality of the sampling distribution. D No, the distribution of the sample is not normal. E

In the US, the average one-way commuting time is 26.4 minutes. Is this different in Atlanta? One survey of 35 Atlanta commuters found an average one-way commuting time of 30.7 minutes. (a) The test statistic is 1.1846. What is the meaning of this test statistic? The average error between different sample results and the hypothesized mean is 1.1846.The current sample result is 1.1846 standard errors above the hypothesized mean.     The maximum error between different sample results and the hypothesized mean is 1.1846. (b) Based on the test statistic of 1.1846, what is the p-value to test if the average commuting time in Atlanta is different than the rest of the US? (4 decimals.) (c) On the basis of the above p-value, what can be said regarding a 95% confidence interval for the true average commuting time? The interval     contain the value 26.4, because this value     . (d) Suppose the sample size was increased to 120 Atlanta commuters, with other values remaining the same. How would…