DATAfile: ComputerNews You may need to use the appropriate appendix table or technology to answer this question. The American Press Institute reports that almost 70% of all American adults use a computer to gain access to news. Based on generational differences, you suspect that the proportion of American adults under 30 years old who use a computer to gain access to news exceeds the proportion of Americans 30 years and older who use a computer to gain access to news. Data in the file ComputerNews represent responses to the question, "Do you use a computer to gain access to news?" given by random samples of American adults under 30 years old and Americans 30 years and older. (a) Estimate the proportion of American adults under 30 years old who use a computer to gain access to news and the proportion of Americans 30 years and older who use a computer to gain access to news. (Round your answers to three decimal places.) American adults under 30 years old Americans 30 years and older 325 675 (b) Provide a 95% confidence interval for the difference in proportions between American adults under 30 years old who use a computer to gain access to news and Americans 30 years and older who use a computer to gain access to news. (Round your answers to four decimal places.) 449 x to -2551 (c) On the basis of your findings, does it appear the proportion of American adults under 30 years old who use a computer to gain access to news exceeds the proportion of Americans 30 years and older who use a computer to gain access to news? Select, because the 95% confidence interval -Select- zero 1 Do you use a computer to gain access to news? 2 Under 30 30 and Older 3 No Yes 4 Yes No 5 Yes Yes 10 6 Yes No 7 Yes No 8 No Yes 9 Yes Yes 10 Yes Yes 11 Yes No 12 Yes Yes 13 No No 14 No Yes 15 Yes No 16 Yes Yes 17 Yes No 18 Yes Yes 19 Yes Yes 31 34 222222222225233 20 Yes No 21 Yes Yes Yes Yes Yes Yes 24 Yes No Yes Yes 26 No Yes 27 Yes Yes 28 No Yes 29 Yes No 30 Yes Yes No Yes Yes No Yes Yes Yes Yes 35 No No 36 Yes Yes 37 Yes Yes 38 No Yes 39 Yes No 40 Yes Yes 41 Yes Yes 42 Yes No 43 Yes Yes 44 Yes Yes 45 Yes No 46 Yes Yes 47 No Yes 48 Yes Yes 49 Yes No 50 Yes No 51 Yes Yes 52 Yes No 53 No Yes 54 Yes Yes 55 No Yes 56 Yes No 57 Yes No 58 No No 59) Yes No 60 Yes No 61 No Yes 62 Yes No 63 No Yes 64 Yes No 65 Yes No 66 Yes Yes 67 No No 68 Yes No No No 76 78 79 80 81 82 83 84 85 86 87 88 REEFERRER2222222 70 Yes Yes Yes No 72 No No No Yes 74 Yes Yes 75 No Yes Yes No Yes No Yes No Yes Yes No No Yes No Yes No Yes No Yes No Yes Yes No No Yes Yes No No 89 Yes Yes 90 No No 91 No Yes 92 Yes Yes 93 Yes No 94 Yes No 95 Yes Yes 96 Yes No 97 Yes No 98 Yes Yes 99 Yes No 100 Yes No 101 Yes No 102 Yes No 22 103 Yes Yes 104 Yes No. 105 Yes Yes 106 No Yes 107 Yes Yes 108 No Yes 109 Yes Yes 110 Yes Yes 111 Yes No 112 No Yes 113 Yes Yes 114 No Yes 115 Yes No 116 Yes Yes 117 No No 118 No Yes 119 Yes No 120 Yes Yes 121 No Yes 122 No No 123 Yes Yes 124 No Yes 125 Yes No 126 Yes No 127 Yes No 128 No Yes 129 Yes Yes 130 No Yes 131 Yes Yes 132 Yes Yes 133 Yes Yes 134 No No 135 Yes 136 Yes 22 No No 137 Yes Yes 138 Yes Yes 139 No No 140 Yes Yes. 141 No Yes 142 Yes No 143 Yes Yes 144 Yes Yes 145 Yes No 146 No Yes 147 Yes No 148 Yes Yes 149 Yes No 150 Yes Yes 151 Yes Yes 152 No No 153 No 154 Yes 155 Yes 156 No 157 No 158 No 159 No 160 No 161 Yes 162 No 163 Yes 164 No 165 Yes 166 Yes 167 Yes 168 Yes 169 No 170 Yes 171 172 Yes No 173 No 174 Yes 175 Yes 176 No 177 No 178 Yes 179 Yes 180 No 181 No 182 Yes 183 184 No- Yes 185 Yes 186 No 187 Yes 188 Yes 189 No 190 Yes 191 Yes 192 No 193 No 194 No 195 Yes 196 No 197 Yes 198 Yes 199 Yes 200 Yes 201 Yes 202 No 203 204 TABLE 1 CUMULATIVE PROBABILITIES FOR THE STANDARD NORMAL DISTRIBUTION Cumulative probability 0 Entries in the table give the area under the curve to the left of the z value. For example, for z=-85, the cumulative probability is .1977. .00 .01 .02 .03 .04 .05 .06 .07 .08 .09 -3.0 0013 0013 .0013 .0012 0012 0011 0011 0011 .0010 0010 -2.9 .0019 0018 0018 0017 .0016 .0016 .0015 .0015 .0014 .0014 -2.8 .0026 .0025 .0024 .0023 .0023 0022 .0021 0021 0020 .0019 -2.7 0035 0034 .0033 0032 .0031 0030 0029 0028 0027 .0026 -2.6 .0047 .0045 .0044 0043 .0041 .0040 0039 0038 .0037 .0036 -25 .0062 .0060 .0059 .0057 .0055 0054 0052 0051 .0049 .0048 -2.4 .0082 .0080 .0078 0075 0073 0071 0069 .0068 0066 .0064 -2.3 .0107 .0104 0102 .0099 0096 0094 .0091 .0089 .0087 .0084 -2.2 0139 0136 .0132 0129 0125 0122 0119 0116 0113 0110 -2.1 .0179 0174 .0170 .0166 0162 0158 0154 0150 .0146 0143 -2.0 .0228 0222 .0217 0212 0207 .0202 0197 0192 0188 0183 -1.9 0287 .0281 .0274 0268 0262 0256 0250 0244 0239 0233 -1.8 .0359 0351 0344 0336 0329 0322 0314 0307 0301 0294 -1.7 0446 .0436 0427 0418 0409 0401 .0392 0384 0375 .0367 -1.6 0548 .0537 0526 .0516 .0505 0495 .0485 0475 0465 .0455 -1.5 .0668 .0655 .0643 .0630 .0618 0606 0594 .0582 0571 .0559 -14 .0808 0793 0778 0764 0749 0735 0721 0708 0694 .0681 -1.3 .0968 .0951 0934 0918 0901 0885 0869 0853 0838 0823 -1.2 1151 .1131 1112 .1093 1075 .1056 .1038 1020 .1003 .0985 -1.1 .1357 1335 1314 1292 1271 1251 .1230 .1210 1190 1170 -1.0 1587 .1562 1539 1515 .1492 1469 1446 1423 1401 1379 -9 .1841 .1814 1788 .1762 1736 .1711 .1685 1660 .1635 .1611 -8 2119 2090 2061 2033 2005 1977 1949 .1922 .1894 .1867 -.7 2420 2389 2358 2327 2296 2266 2236 2206 2177 2148 -.6 2743 2709 2676 2643 2611 2578 2546 2514 2483 2451 -5 3085 3050 3015 2981 2946 2912 2877 2843 2810 2776 77778 -4 3409 3446 .3372 .3336 3300 3264 3228 3192 3156 3121 -3 .3821 3783 3745 3707 3669 3632 3594 3557 3520 3483 -2 4207 4168 4129 4090 4052 4013 3974 3936 3897 3859 -J 4602 4562 4522 4483 4443 4404 4364 4325 4286 4247 -.0 5000 4960 4920 4880 4840 4801 4761 4721 4681 4641 Z Cumulative probability Entries in the table give the area under the curve to the left of the z value. For example, for z=1.25, the cumulative probability is .8944. Z .00 .01 .02 .03 .04 .05 .06 .07 .08 .09 01334 .5000 5040 5080 .5120 5160 5199 5239 5279 5319 5359 .5398 5438 5478 .5517 5557 5596 5636 5675 5714 5753 .5793 5832 5871 .5910 5948 5987 .6026 .6064 .6103 .6141 .6179 .6217 .6255 .6293 .6331 .6368 .6406 .6443 .6480 .6517 .6554 .6591 .6628 .6664 .6700 .6736 .6772 .6808 .6844 .6879 56589 .6915 .6950 .6985 .7019 .7054 7088 .7123 .7157 .7190 7224 .6 .7257 .7291 7324 .7357 .7389 .7422 .7454 .7486 .7517 .7549 .7580 .7611 .7642 .7673 .7704 .7734 .7764 .7794 .7823 .7852 .7881 .7910 .7939 .7967 .7995 .8023 .8051 .8159 .8186 .8212 .8238 .8264 .8289 .8315 8078 .8106 .8133 .8340 .8365 8389 1.1 1.6 2256789 1.0 .8413 .8438 .8461 .8485 .8508 .8531 .8554 .8577 .8599 .8621 .8643 8665 .8686 .8708 8729 8749 .8770 .8790 .8810 .8830 1.2 .8849 8869 8888 .8907 .8925 .8944 .8962 .8980 .8997 .9015 1.3 .9032 9049 9066 1.4 .9192 .9207 9222 9082 9099 9115 .9131 9147 9162 .9177 9236 9251 9265 9279 9292 9306 9319 1.5 .9332 .9345 9357 9474 1.8. 1.9 9713 .9641 .9649 .9656 .9664 .9719 .9726 9732 .9370 .9382 9394 9406 9452 .9463 .9484 9495 .9505 .9515 1.7 .9554 9564 .9573 9582 .9591 .9599 .9608 9671 .9678 .9686 9693 9738 9744 9750 9756 9418 9429 9441 9525 9535 9545 9616 .9625 9633 9699 9706 9761 9767 2.3 22222 2.0 9772 .9778 9783 9788 9793 9798 .9803 9808 9812 9817 2.1 .9821 .9826 9830 .9834 .9838 98421 .9846 9850 9854 9857 .9861 9864 9868 .9871 .9875 9878 .9881 .9884 .9887 .9890 .9893 .9896 9898 9901 9904 9906 .9909 .9911 9913 9916 2.4 .9918 .9920 9922 .9925 .9927 9929 .9931 9932 9934 9936 2222N 2.5 2.6 Jay .9938 .9940 9941 .9943 9945 9946 .9948 9949 9951 9952 .9953 9955 9956 .9957 .9959 .9960 .9961 .9962 9963 9964 2.7 .9965 2.8 .9966 9974 9975 .9976 9977 .9967 9968 9969 9970 .9971 .9977 9978 9972 9973 9974 .9979 9979 9980 9981 2.9 .9981 9982 .9982 .9983 9984 9984 9985 9985 9986 9986 3.0 9987 .9987 .9987 .9988 .9988 .9989 .9989 .9989 9990 9990 Degrees Area in Upper Tail of Freedom .20 .10 .05 .025 .01 .005 1234 56789 1.376 3.078 6.314 12.706 31.821 63.656 1.061 1.886 2.920 4.303 6.965 9.925 .978 1.638 2.353 3.182 4.541 5.841 .941 1.533 2.132 2.776 3.747 4.604 .920 1.476 2.015 2.571 3.365 4.032 .906 1.440 1.943 2.447 3.143 3.707 .896 1.415 1.895 2.365 2.998 3.499 .889 1.397 1.860 2.306 2.896 3.355 .883 1.383 1.833 2.262 2.821 3.250 28 31 34 CHERY READ 22222 22233 10 .879 1.372 1.812 2.228 2.764 3.169 11 .876 1.363 1.796 2,201 2.718 3.106 12 .873 1.356 1.782 2.179 2.681 3.055 13 .870 1.350 1.771 2.160 2.650 3.012 14 .868 1.345 1.761 2.145 2.624 2.977 15 .866 1.341 1.753 2.131 2.602 2.947 16 .865 1.337 1.746 2.120 2.583 2.921 17 .863. 1.333 1.740 2.110 2.567 2.898 18 .862 1.330 1.734 2.101 2.552 2.878 19 .861 1.328 1.729 2.093 2.539 2.861 20 .860 1.325 1.725 2.086 2.528 2.845 21 .859 1.323 1.721 2.080 2.518 2.831 22 .858 1.321 1.717 2.074 2.508 2.819 23 .858 1.319 1.714 2.069 2.500 2.807 24 .857 1.318 1.711 2.064 2.492 2.797 25 .856 1.316 1.708 2.060 2.485 2.787 26 .856 1.315 1.706 2.056 2.479 2.779 27 .855 1.314 1.703 2.052 2.473 2.771 .855 1.313 1.701 2.048 2.467 2.763 29 .854 1.311 1.699 2.045 2.462 2.756 30 .854 1.310 1.697 2.042 2.457 2.750 .853 1.309 1.696 2.040 2.453 2.744 .853 1.309 1.694 2.037 2.449 2.738 .853 1.308 1.692 2.035 2.445 2.733 .852 1.307 1.691 2.032 2.441 2.728 Degrees of Freedom Area in Upper Tail .20 .10 .05 .025 .01 .005 35 .852 1.306 36 1.690 2.030 .852 2.438 1.306 2.724 1.688 37 2.028 851 2.434 2.719 1.305 1.687 38 2.026 .851 2.431 1.304 2.715 39 1.686 2.024 2.429 .851 2.712 1.304 1.685 2.023 2.426 2.708 40 .851 1.303 1.684 71 72 75 76 **** ****** 85823 38533 REFERR 41 2.021 2.423 850 2.704 1.303 1.683 42 2.020 2.421 .850 2.701 1.302 1.682 2.018 43 2.418 .850 2.698 1.302) 1.681 2.017 44 2.416 2.695 .850 1.301 1.680 2.015 2.414 2.692 45 .850 1.301 1.679 2.014 46 2.412 2.690 .850 1.300 1.679 2.013 2.410 47 2.687 .849 1.300 1.678 2.012 2.408 2.685 48 .849 1.299 1.677 2.011 2.407 2.682 49 .849 1.299 1.677 2.010 2.405 2.680 50 .849 1.299 1.676 2.009 2.403 2.678 51 .849 1.298 1.675 2.008 2.402 2.676 52 .849 1.298 1.675 2.007 2.400 2.674 53 848 1.298 1.674 2.006 2.399 2.672 54 .848 1.297 1.674 2.005 2.397 2.670 55 .848 1.297 1.673 2.004 2.396 2.668 56 .848 1.297 1.673 2.003 2.395 2.667 .848 1.297 1.672 2.002 2.394 2.665 58 .848 1.296 1.672 2.002 2.392 2.663 .848 1.296 1.671 2.001 2.391 2.662 60 .848 1.296 1.671 2.000 2.390 2.660 61 .848 1.296 1.670 2.000 2.389 2.659 62 .847 1.295 1.670 1.999 2.388 2.657 63 .847 1.295 1.669 1.998 2.387 2.656 64 .847 1.295 1.669 1.998 2.386 2.655 65 .847 1.295 1.669 1.997 2.385 2.654 66 .847 1.295 1.668 1.997 2.384 2.652 67 .847 1.294 1.668 1.996 2.383 2.651 68 .847 1.294 1.668 1.995 2.382 2.650 69 .847 1.294 1.667 1.995 2.382 2.649 70 .847 1.294 1.667 1.994 2.381 2.648 .847 1.294 1.667 1.994 2.380 2.647 .847 1.293 1.666 1.993 2.379 2.646 73 .847 1.293 1.666 1.993 2.379 2.645 74 .847 1.293 1.666 1.993 2.378 2.644 .846 1.293 1.665 1.992 2.377 2.643 .846 1.293 1.665 1.992 2.376 2.642 1001 3226 2641 Appendix B Tables TABLE 2 DISTRIBUTION (Continued) Degrees of Freedom Area in Upper Tail .20 .10 .05 .025 .01 .005 80 .846 1.292 1.664 1.990 2.374 2.639 81 .846 1.292 1.664 1.990 2.373 2.638 82 83 23 .846 1.292 1.664 1.989 2.373 2.637 .846 1.292 1.663 1.989 2.372 2.636 84 .846 1.292 1.663 1.989 2.372 2.636 100 22222222288 85 .846 1.292 1.663 1.988 2.371 2.635 86 .846 1.291 1.663 1.988 2.370 2.634 87 .846 1.291 1.663 1.988 2.370 2.634 .846 1.291 1.662 1.987 2.369 2.633 89 .846 1.291 1.662 1.987 2.369 2.632 .846 1.291 1.662 1.987 2.368 2.632 91 .846 1.291 1.662 1.986 2.368 2.631 92 .846 1.291 1.662 1.986 2.368 2.630 .846 1.291 1.661 1.986. 2.367 2.630 94 .845 1.291 1.661 1.986 2.367 2.629 .845 1.291 1.661 1.985 2.366 2.629 .845 1.290 1.661 1.985 2.366 2.628 .845 1.290 1.661 1.985 2.365 2.627 .845 1.290 1.661 1.984 2.365 2.627 .845 1.290 1.660 1.984 2.364 2.626 .845 1.290 1.660 1.984 2.364 2.626 .842 1.282 1.645 1.960 2.326 2.576