1 of 20 1.0 Points Which of the following values is not typically used for f$alpha f$ ? A.0.05 B.0.50 C.0.10 D.0.01 Reset Selection Question 2 of 20 1.0 Points The Pizza Hot manager commits a Type I error if he/she is A.staying with old style when new style is better B.switching to new style when it is better than old style C.switching to new style when it is no better than old style D.staying with old style when new style is no better than old style Reset Selection Question 3 of 20 1.0 Points In an article appearing in Todays Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7. State the null and alternative hypotheses. A.H0: \f$\mu \f$ \f$\geq \f$ 75, H1: \f$\mu \f$ < 75 B.H0: \f$\mu \f$ = 75, H1: \f$\mu \f$ 75 C.H0: \f$\mu \f$ = 75, H1: \f$\mu \f$ > 75 D.H0: \f$\mu \f$ \f$\leq \f$ 75, H1: \f$\mu \f$ > 75 Reset Selection Question 4 of 20 1.0 Points A type I error occurs when the: A.null hypothesis is incorrectly rejected when it is true B.sample mean differs from the population mean C.test is biased D.null hypothesis is incorrectly accepted when it is false Reset Selection Question 5 of 20 1.0 Points A null hypothesis can only be rejected at the 5% significance level if and only if: A.the null hypothesis is biased B.the null hypotheses includes sampling error C.a 95% confidence interval does not include the hypothesized value of the parameter D.a 95% confidence interval includes the hypothesized value of the parameter Reset Selection Question 6 of 20 1.0 Points Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance. State the null and alternative hypotheses. A.H0: p = .79, H1: p .79 B.H0: p .79, H1: p > .79 C.H0: m = .79, H1: m > .79 D. H0: \f$\hat{p}\f$ = .79, H1: \f$\hat{p}\f$ > .79 Reset Selection Question 7 of 20 1.0 Points In an article appearing in Todays Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7. Compute the z or t value of the sample test statistic. A.z = 1.645 B.t = 1.916 C.t = -1.916 D.z = 1.916 Reset Selection Question 8 of 20 1.0 Points A two-tailed test is one where: A.results in either of two directions can lead to rejection of the null hypothesis B.results in only one direction can lead to rejection of the null hypothesis C.no results lead to the rejection of the null hypothesis D.negative sample means lead to rejection of the null hypothesis Reset Selection Question 9 of 20 1.0 Points Suppose that the mean time for a certain car to go from 0 to 60 miles per hour was 7.7 seconds. Suppose that you want to test the claim that the average time to accelerate from 0 to 60 miles per hour is longer than 7.7 seconds. What would you use for the alternative hypothesis? A.H1: \f$\mu \geq \f$ 7.7 seconds B.H1: \f$\mu \f$ < 7.7 seconds C.H1: \f$\mu \f$ = 7.7 seconds D.H1: \f$\mu \f$ > 7.7 seconds Reset Selection Question 10 of 20 1.0 Points The null and alternative hypotheses divide all possibilities into: A.two non-overlapping sets B.two sets that may or may not overlap C.two sets that overlap D.as many sets as necessary to cover all possibilities Reset Selection Question 11 of 20 1.0 Points A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technicians accuracy is within the target accuracy? State the null and alternative hypotheses. A.H0: s2 < 1.2, H1: s2 1.2 B.H0: s2 1.2, H1: s2 1.2 C.H0: s2 1.2, H1: s2 = 1.2 D.H0: s2 1.2, H1: s2 > 1.2 Reset Selection Part 2 of 3 - Question 12 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A statistician wishes to test the claim that the standard deviation of the weights of firemen is greater than 25 pounds. To do so, she selected a random sample of 20 firemen and found s = 27.2 pounds. Assuming that the weights of firemen are normally distributed, to test her research hypothesis the statistician would use a chi-square test. In that case, what is the computed test value? Place your answer, rounded to 3 decimal places, in the blank. For example, 23.456 would be a legitimate entry. Question 13 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A medical doctor wishes to test the claim that the standard deviation of the systolic blood pressure of deep sea divers is greater than 450. To do so, she selected a random sample of 25 divers and found s = 468. Assuming that the systolic blood pressures of deep sea divers are normally distributed, the doctor would perform a chi-square test to test her research hypothesis. In that case, what is the test value that she would compute. Place your answer, rounded to 3 decimal places, in the blank. For example, 34.567 would be a legitimate entry. Question 14 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A firm that produces light bulbs claims that their lightbulbs last 1500 hours, on average. You wonder if the average might differ from the 1500 hours that the firm claims. To explore this possibility you take a random sample of n = 25 light bulbs purchased from this firm and record the lifetime (in hours) of each bulb. You then conduct an appopriate test of hypothesis. Some of the information related to the hypothesis test is presented below. Test of H0: f$mu f$ = 1500 versus H1: f$ mu eq f$ 1500 Sample mean 1509.5 Std error of mean 4.854 Assuming the life length of this type of lightbulb is normally distributed, what is the p-value associated with this test? Place your answer, rounded to 3 decimal places, in the blank. For example, 0.234 would be a legitimate entry. Question 15 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The ABC battery company claims that their batteries last at least 100 hours, on average. Your experience with their batteries has been somewhat different, so you decide to conduct a test to see if the company's claim is true. You believe that the mean life is actually less than the 100 hours the company claims. You decide to collect data on the average battery life (in hours) of a random sample of n = 20 batteries. Some of the information related to the hypothesis test is presented below. Test of H0: f$mu geq f$ 100 versus H1: f$mu < f$ 100 Sample mean 98.5 Std error of mean 0.777 Assuming the life length of batteries is normally distributed, what is the value of the test statistic used to conduct your test of hypothesis? Place your answer, rounded to 3 decimal places in the blank. For example, -2.345 would be a legitimate entry. Question 16 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A survey determines that mint chocolate chip is the favorite ice cream flavor of 6% of consumers. An ice cream shop determines that of 260 customers, 20 customers stated their preference for mint chocolate chip. Find the P-value that would be used to determine if the percentage of customers who prefer mint chocolate chip ice has increased at a 5% level of significance. P-value: Round your answer to four decimal places as necessary. Question 17 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Suppose a firm that produces light bulbs wants to know whether it can say that its light bulbs typically last more than 1500 hours. Hoping to find support for their claim, the firm collects a random sample of n = 25 light bulbs and records the lifetime (in hours) of each bulb. The information related to the hypothesis test is presented below. Test of H0: f$mu leq f$ 1500 versus H1: f$ mu f$ > 1500 Sample mean 1509.5 Std error of mean 4.854 Assuming the life length of this type of lightbulb is normally distributed, what is the p-value associated with this test? Place your answer, rounded to 3 decimal places in the blank. For example, .123 would be a legitimate entry. Part 3 of 3 - Question 18 of 20 1.0 Points If a null hypothesis about a population proportion p is rejected at the 0.025 level of significance, then it must also be rejected it at the 0.05 level. True False Reset Selection Question 19 of 20 1.0 Points The probability of making a Type I error and the level of significance are the same. True False Reset Selection Question 20 of 20 1.0 Points The smaller the pvalue, the more evidence there is in favor of the alternative hypothesis. True False Reset Selection