- Determine The T Value In Each Of The Cases Click The Icon To View The Table Of Areas Under The T Distribution A Find 1 (56.56 KiB) Viewed 31 times
X 1 Table of t-Distribution Areas S -Area in right tail Table VI t-Distribution Area in Right Tail df 0.25 0.20 0.15 0.10 0.05 0.025 0.02 0.01 0.005 0.0025 0.001 0.000 1 2 3 4 5 6 7 1.000 0.816 0.765 0.741 0.727 0.718 0 711 1.376 1.061 0.978 0.941 0.920 0.906 0896 1.963 1.386 1.250 1.190 1.156 1.134 1 119 3.078 1.886 1.638 1.533 1.476 1.440 1415 6.314 2.920 2.353 2.132 2.015 1.943 1 895 12.706 4.303 3.182 2.776 2.571 2.447 2.365. 15.894 4.849 3.482 2.999 2.757 2.612 2517 31.821 6.965 4.541 3.747 3.365 3.143 2998 63.657 9.925 5.841 4.604 4.032 3.707 3499 127.321 14.089 7.453 5.598 4.773 4.317 4029 318.309 22.327 10.215 7.173 5.893 5.208 4 785 636.6 31.5 12.9 8.6 6.8 5.9 54
A simple random sample of size n is drawn from a population that is normally distributed. The sample mean, x, is found to be 105, and the sample standard deviation, s, is found to be 10. (a) Construct a 95% confidence interval about u if the sample size, n, is 19. n, (b) Construct a 95% confidence interval about u if the sample size, n, is 15. (c) Construct a 70% confidence interval about u if the sample size, n, is 19. (d) Could we have computed the confidence intervals in parts (a)-(c) if the population had not been normally distributed? Click the icon to view the table of areas under the t-distribution. (a) Construct a 95% confidence interval about u if the sample size, n, is 19. Lower bound: ; Upper bound: (Use ascending order. Round to one decimal place as needed.)
x Table of t-Distribution Areas Area in right tail Table VI t-Distribution Area in Right Tail df 0.25 0.20 0.15 0.10 0.05 0.025 0.02 0.01 0.005 0.0025 0.001 0.000 1 2 3 4 5 1.000 0.816 0.765 0.741 0.727 0.718 0 711 1.376 1.061 0.978 0.941 0.920 0.906 0896 1.963 1.386 1.250 1.190 1.156 1.134 1119 3.078 1.886 1.638 1.533 1.476 1.440 1415 6.314 2.920 2.353 2.132 2.015 1.943 1 895 12.706 4.303 3.182 2.776 2.571 2.447 2365 15.894 4.849 3.482 2.999 2.757 2.612 2517 31.821 6.965 4.541 3.747 3.365 3.143 2998 63.657 9.925 5.841 4.604 4.032 3.707 3.499 127.321 14.089 7.453 5.598 4.773 4.317 4029 318.309 22.327 10.215 7.173 5.893 5.208 4785 636.6 31.5 12.9 8.6 6.8 5.9 54 6 7
The trade magazine QSR routinely checks the drive-through service times of fast-food restaurants. A 99% confidence interval that results from examining 782 customers in Taco Bell's drive-through has a lower bound of 165.9 seconds and an upper bound of 172.3 seconds. Complete parts (a) through (c). (a) What is the mean service time from the 782 customers? The mean service time from the 782 customers is 169.1 seconds (Type an integer or a decimal. Do not round.) (b) What is the margin of error for the confidence interval? The margin of error is seconds. (Type an integer or a decimal. Do not round.)
The following data represent the pH of rain for a random sample of 12 rain dates. A normal probability plot suggests the data could come from a population that is normally distributed. A boxplot indicates there are no outliers. Complete parts a) through d) below. 5.20 5.02 5.43 5.72 4.58 4.76 4.38 4.74 4.56 4.80 5.19 5.71 Click the icon to view the table of critical t-values. (a) Determine a point estimate for the population mean. A point estimate for the population mean is (Round to two decimal places as needed.)
Table of Critical t-Values Area in Tight tail Degrees of Freedom t-Distribution Area in Right Tail 0.05 0.025 0.02 0.25 0.20 0.15 0.10 0.01 0.005 0.0025 0.001 0.0005 1 2 3 5 10 1.000 0.816 0.765 0.741 0.727 0.718 0.711 0.706 0.703 0.700 0.697 0.695 0.694 0.692 0.691 0.690 0.689 0.688 0.688 0.687 67890 12346 67203 1.376 1.061 0.978 0.941 0.920 0.906 0.896 0.889 0.883 0.879 0.876 0.873 0.870 0.868 0.866 0.865 0.863 0.862 0.861 0.860 1.963 1.386 1.250 1.190 1.156 1.134 1.119 1.108 1.100 1.093 1.088 1.083 1.079 1.076 1.074 1.071 1.069 1.067 1.066 1.064 3.078 1.886 1.638 1.533 1.476 1.440 1.415 1.397 1.383 1.372 1.363 1.356 1.350 1.345 1.341 1.337 1.333 1.330 1.328 1.325 6.314 2.920 2.353 2.132 2.015 1.943 1.895 1.860 1.833 1.812 1.796 1.782 1.771 1.761 1.753 1.746 1.740 1.734 1.729 1.725 12.706 4.303 3.182 2.776 2.571 2.447 2.365 2.306 2.262 2.228 2.201 2.179 2.160 2.145 2.131 2.120 2.110 2.101 2.093 2.086 15.894 4.849 3.482 2.999 2.757 2.612 2.517 2.449 2.398 2.359 2.328 2.303 2.282 2.264 2.249 2.235 2.224 2.214 2.205 2.197 31.821 6.965 4.541 3.747 3.365 3.143 2.998 2.896 2.821 2.764 2.718 2.681 2.650 2.624 2.602 2.583 2.567 2.552 2.539 2.528 63.657 9.925 5.841 4.604 4.032 3.707 3.499 3.355 3.250 3.169 3.106 3.055 3.012 2.977 2.947 2.921 2.898 2.878 2.861 2.845 127.321 14.089 7453 5.598 4.773 4.317 4.029 3.833 3.690 3.581 3.497 3.428 3.372 3.326 3.286 3.252 3.222 3.197 3.174 3.153 318.309 636.619 22.327 31.599 10.215 12.924 7173 8.610 5.893 6.869 5.208 5.959 4.785 5.408 4.501 5.041 4.297 4.781 4.144 4.587 4.025 4.437 3.930 4.318 3.852 4.221 3.787 4.140 3.733 4.073 3.686 4.015 3.646 3.965 3.610 3.922 3.579 3.883 3.552 3.850 11 15 16 17 18 19
The trade volume of a stock is the number of shares traded on a given day. The data in the first accompanying table, in millions (so that 6.16 represents 6,160,000 shares traded), represent the volume of a PepsiCo stock traded for a random sample of 38 trading days in 2018. A second random sample of 38 days in 2018 resulted in the data in the second accompanying table. Complete parts (a) through (d). Click here to view the data for sample 1. Click here to view the data for sample 2. Click here to view the table of critical t-values. (a) Use the data from sample 1 to compute a point estimate for the population mean number of shares traded per day in 2018. million. A point estimate for the population mean number of PepsiCo shares traded per day in 2018 is (Round to two decimal places as needed.)
< > Sample 1 Volumes (millions) Sample 1 6.16 4.16 4.98 7.54 5.55 8.88 4.28 7.56 7.28 6.10 6.39 4.00 4.02 6.22 4.35 4.64 6.69 6.96 5.32 6.71 5.05 2.37 4.95 4.13 4.42 6.67 4.92 6.23 4.41 7.71 4.97 7.29 5.07 3.94 4.80 5.04 6.92 2.42
< Sample 2 Volumes (millions) Sample 2 6.12 10.96 4.49 5.27 8.57 7.65 3.65 4.96 6.89 3.79 5.73 4.54 6.34 4.85 3.65 8.13 4.80 5.14 5.08 5.75 6.85 5.46 5.90 4.81 3.39 6.69 8.37 7.84 5.00 6.04 5.44 6.58 5.99 6.74 5.68 4.37 4.89 3.71
- Table of Critical t-Values m Де- Area in right tail Table VII Degrees of Freedom t-Distribution Area in Right Tail 0.025 0.02 0.25 0.20 0.15 0.10 0.05 0.01 0.005 0.0025 0.001 0.0005 1 2 3 4 5 6 7 8 9 10 1.000 0.816 0.765 0.741 0.727 0.718 0.711 0.706 0.703 0.700 0.697 0.695 0.694 0.692 0.691 1.376 1.061 0.978 0.941 0.920 0.906 0.896 0.889 0.883 0.879 0.876 0.873 0.870 0.868 0.866 1.963 1.386 1.250 1.190 1.156 1.134 1.119 1.108 1.100 1.093 1.088 1.083 1.079 1.076 1.074 3.078 1.886 1.638 1.533 1.476 1.440 1.415 1.397 1.383 1.372 1.363 1.356 1.350 1.345 1.341 6.314 2.920 2.353 2.132 2.015 1.943 1.895 1.860 1.833 1.812 1.796 1.782 1.771 1.761 1.753 12.706 4.303 3.182 2.776 2.571 2.447 2.365 2.306 2.262 2.228 2.201 2.179 2.160 2.145 2.131 15.894 4.849 3.482 2.999 2.757 2.612 2.517 2.449 2.398 2.359 2.328 2.303 2.282 2.264 2.249 31.821 6.965 4.541 3.747 3.365 3.143 2.998 2.896 2.821 2.764 2.718 2.681 2.650 2.624 2.602 63.657 9.925 5.841 4.604 4.032 3.707 3.499 3.355 3.250 3.169 3.106 3.055 3.012 2.977 2.947 127.321 14.089 7.453 5.598 4.773 4.317 4.029 3.833 3.690 3.581 3.497 3.428 3.372 3.326 3.286 318.309 22.327 10.215 7.173 5.893 5.208 4.785 4.501 4.297 4.144 4.025 3.930 3.852 3.787 3.733 636.619 31.599 12.924 8.610 6.869 5.959 5.408 5.041 4.781 4.587 4.437 4.318 4.221 4.140 4.073 11 12 13 14 15
A doctor wants to estimate the mean HDL cholesterol of all 20- to 29-year-old females. How many subjects are needed to estimate the mean HDL cholesterol within 3 points with 99% confidence assuming s = 13.2 based on earlier studies? Suppose the doctor would be content with 95% confidence. How does the decrease in confidence affect the sample size required? Click the icon to view a partial table of critical values. A 99% confidence level requires subjects. (Round up to the nearest subject.)
Partial Critical Value Table OC Critical Value, Za/2 Area in Each Tail, 2 Level of Confidence, (1 - a) • 100% 90% 95% 99% 0.05 0.025 0.005 1.645 1.96 2.575
People were polled on how many books they read the previous year. Initial survey results indicate that s = 10.4 books. Complete parts (a) through (d) below. Click the icon to view a partial table of critical values. (a) How many subjects are needed to estimate the mean number of books read the previous year within four books with 95% confidence? This 95% confidence level requires subjects. (Round up to the nearest subject.)
Partial Critical Value Table Critical Value, za/2 Level of Confidence, (1 - a). 100% - 90% 95% 99% a Area in Each Tail, 2 0.05 0.025 0.005 1.645 1.96 2.575