Question

Wong to the real question prevents changes to this answer Question 5 of Question 5 5 points Save Answer Suppose that andom samo 10 deseas and the concert corresponding to the mean height (inches) was found the confidence interval was Cated to be on the devono 26 ches What is the confidence level as a percentage corresponding to this confidence interval?

Answer 1

Solution :

Solution - Q5:- Here we have given that n =10 r = 2.6 inches. so is known ( popul^ S.D) so confidence interval is. X-Zx/e <l< ²+ Zah We have given confidence interval. (63.1, 65.3) Now, substract upper CI to Lower CI 4+ 24/2 T X + 2x/2 in = 65.3 -63.11 2 7% 2.2 Z/ 2.2 Zx/t 2.6 Vio Zato 1.338 Zab 1.34 from Normal table, z-score 1.34 coresponding is o.ogol so - O.ogol probability 2

so, 2 *0.ogol x = 0.18 18% So, the confidence level corresponding to given confidence interval is 184 > Here given that Here number of sample 'n'= 126 climbers & X = 46 College graduate's. so, Proportion is xe 46 126 0.365 We have to find the Lowe e confidence limit foo for proportion confidence interval. frormula of proportion cI is; Êt Zal FÅ CI-4 Lower limit is in fa Zatz ACRÉ Where x is confidence level. ar level of significance (1-2% confidence interval

We have go% go% confidence interval (1-0.90) = ogo so, Lowee limit! 0.365 - 20.05 0.365 (1-0.365) 126 from Normal table Zo.05 1.64 ( probability 0.05 corresponding Z-Scores 1.64 So, = 0.365 - 1.64 * 0.042889 = 0.2946 lowed limit = 0.295 ł 0.30 (in two decimal places lower limit of go% CI for the proportion of mourtain climbers who are College graduates is

Q2]:- Here sample obser loo n=100 Popul standard deviation co= 40 & sample mean (x) = 240 We have to find lower limit of 70 % confidence interval of the population mean, - 0.30 & x/2 = 0.15 and from Normal table. Zo/2 = Zous ~ 1.04 fromula of confidence interval is; X-22 / = Lowed limiti lower limit 240 - 1.04 * 40 Vioo = 235.84 (I of the → Lower limit of 70% mean is 235.84 population 236

From all above example there is need of Normal table for finding Z- Score probability

So, Normal table is below

z .00 .01 102 .03 104 105 106 107 1.08 .09 0 15000 4960 4920 4880 4840 4801 4761 4721 14681 4641 11 14602 4562 4522 4483 4443 4404 4364 14325 426 4247 2 4207 4168 4129 4090 4052 4013 13974 13936 13897 13859 3 3821 3783 3745 3707 3669 13632 13594 3557 13520 3483 14 3446 13409 13372 13336 3300 3264 3228 3192 13156 3121 15 13085 13050 3015 2981 2946 2912 2877 2843 12810 12776 6 2743 2709 2676 2643 2611 2578 12546 2514 12483 12451 17 2420 239 12358 12327 2296 2266 2236 12206 12177 2148 18 2119 200 2061 12033 2005 1977 .1949 1922 11894 167 19 11841 1814 1788 1762 1736 1711 .1685 11660 1635 1611 1.0 1587 1562 1539 1515 1492 11469 11446 1423 1401 1379 1.1 1357 1335 1314 1292 (1271 1251 .1230 11210 1190 1170 1.2 1151 1131 1112 1093 1075 1056 .1038 1020 11003 10985 1.3 10968 10951 10934 10918 0901 0885 10869 0853 10838 10823 1.4 0808 0793 10778 0764 0749 0735 0721 10708 0694 0681 1.5 10668 10655 10643 10630 10618 10606 0594 0582 10571 10559 1.6 10548 0537 10526 1.0516 10505 0495 0485 0475 0465 10455 1.7 0446 10436 10427 0418 10409 10401 10392 10384 0375 10367 1.8 0359 10351 0344 0336 10329 10322 0314 10307 1.0301 0294 1.9 0287 0281 10274 10268 10262 10256 0250 0244 0239 10233 2.0 10228 0222 10217 0212 10207 10202 2017 10192 0188 2013 2.1 0179 0174 10170 20162 20158 20154 .0150 016 20143 2.2 0139 0136 20132 20166 20129 20099 20125 0119 0116 0113 0110 20122 20094 2.3 20107 0104 10102 006 20091 0089 20087 20084 2.4 10082 20080 20078 0075 20073 20071 20069 0068 0066 20064 2.5 0062 10060 0059 0057 20055 10054 10052 0051 0049 0048 2.6 10047 10045 10044 0043 0041 0040 20039 10038 0037 20036 2.7 0035 10034 10033 10032 0031 0030 0029 10028 0027 0026 2.8 10026 10025 20024 .0023 10023 10022 10021 20021 0020 0019 2.9 10019 .0018 10018 10017 1.0016 10016 10015 0015 0014 10014 3.0 10013 0013 10013 1.0012 10012 0011 0011 0011 10010 0010 3.1 10010 0009 10009 10009 10008 10008 10008 10008 0007 10007 13.2 10007 0007 10006 10006 10006 10006 10006 0005 10005 10005 3.3 10005 10005 0005 10004 10004 1.0004 10004 0004 10004 10003 3.4 0003 10003 10003 10003 0003 20003 10003 10003 0003 10002