ࡱ> @ bjbjFF .,,[ s B:   $ R: 9 - ;;;  ; ;;B   pNQ"Z  C 0s b ,A1A A @; $1 Twenty-five blood samples were selected by taking every seventh blood sample from racks holding 187 blood samples from the morning draw at a medical center. The white blood count (WBC) was measured using a Coulter Counter Model S. The mean WBC was 8.636 with a standard deviation of 3.9265. (a) Construct a 90 percent confidence interval for the true mean. (b) Why might normality be an issue here? (c) What sample size would be needed for an error of 1.5 with 98 percent confidence? Here it is given that Sample mean, x-bar = 8.636 Sample standard deviation, s = 3.9265 Sample size, n = 25 t-value = 1.711 [From Student s t table with n -1 = 25  1 = 24 degrees of freedom with ( = 0.10] Margin of error, E = t*s/"n = 1.711* (3.9265/(25)= 1.3436 Since the sample size is small (size < 30) we will use the t-distribution to calculate the confidence interval. a) The 90% confidence interval for the true mean is (x-bar E, x-bar + E) = (8.636 - 1.3436, 8.636 + 1.3436) = (7.2924, 9.9796) (b) Normality might be an issue because the sample size is small and we have no idea how the population is distributed. (c) Here it is given that,  EMBED Equation.DSMT4  = 3.9265, E = 1.5,  EMBED Equation.DSMT4 = 2.326 Now, the required sample size, n  ^ ` n t D c d h ο}uuumbubububuuhR0qh?eB* phh?eB*ph33h?eB* phhdB* phhdhdB* ph jhR0qhR0qB* phhR0qhR0qB*CJaJph33# jahR0qhR0qB*CJaJphhR0qhR0qB*CJaJphhR0qB*ph33hR0qhLB* phhR0qhR0qB* phhR0qB* phhLB* phhL" | d f k |gd%Nh dh`gd?edhgdR0qgdL c d e f j k óÜtó]Kt"jhdh%NhB* EHUph,jN hdh%NhB* CJUVaJphhdhdB* phhdhLB* ph"jhdh%NhB* EHUph,jjN hdh%NhB* CJUVaJphjhdh%NhB* Uphhdh%NhB* phhLB* phh?eB*ph33h?ehR0qB* phhR0qhR0qB*ph33h?eh?eB* phe"  EMBED Equation.DSMT4 = (2.326*3.9265/1.5)^2 =37.0832 Thus the required sample size = 38 468:<hjxñhdhhB* phhdhdB* ph"jhdh%NhB* EHUph,j䶗N hdh%NhB* CJUVaJphjhdh%NhB* Uphhdh%NhB* phhdB* phU,1h/ =!"#$% Dd b  c $A? ?3"`?2Ob> yGHCeD`!Ob> yGHCe*`R!xMQ=KA}# h!FɡMB0S" XG,;++B0Y ̛ 2R8cbJ4F_E;fqB=FB'5i:DuJ 8B_q8(Ks |Y-H13a|4vB=K4"WLᵠԂn2<ŊY*-9^q+Uvsή!e3nX bJELMUE. e uب;DDjf׵e̽L?巗lBGg-=I:V3vڶ|M-hiPNIɍV.QG]_#|ke@hF4L/8~t5J/PvDd hb  c $A? ?3"`?2E}jAc!`!}jAc@|xڕRoP9CC`@C{ĢCSE$kHI4UVb ltΞN3!a=;E{}i@;$@`rQHDQMbKH8g` Le|{?3]6ʡՇ`C%H/i/1)#`֛gNo-Ka#aakg$h{S̾OO ~YɰmCt a^d3;N AS5|{LT\_?NEV67Vk5:z6yym]Tn[0WtGS MT_ thcd%iFnୄ#YbYʞ1r}bA陑< RhA6w9&ΫX&ט {UDOL9 7Dd b  c $A? ?3"`?2I1̕ ͪ`!I1̕ ͪ^L (+|xڥTkA~3[4hRBz6Y-HJ0)ULbQ%SAODz It݄,o{< *Pn4Fxe0 ] 9e#|60𤌫r{x | a ! тLhJ2'wrf;95!`ƙ`Y-*,?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abce FMathType 5.0 Equation MathType EFEquation.DSMT49qtDSMT5WinAllBasicCodePagesTimes New RomanSymbolCourier NewMT Extra!/ED/APG_APAPAE%B_AC_AE*_HA@AHA*_D_E_E_A  sEquation Native _1318565510 FpNQpNQOle CompObj i FMathType 5.0 Equation MathType EFEquation.DSMT49qDSMT5WinAllBasicCodePagesTimes New RomanSymbolCourier NewMT Extra!/ED/APG_APAPAE%B_AC_AE*_HA@AHA*_D_E_E_A  z a/2ObjInfo Equation Native  _1318565604FpNQpNQOle  FMathType 5.0 Equation MathType EFEquation.DSMT49q!DSMT5WinAllBasicCodePagesTimes New RomanSymbolCourier NewMT Extra!/ED/APG_APAPAE%B_AC_AE*_HA@AHA*_D_E_ECompObjiObjInfoEquation Native =1Table&Q_A   z a/2 sE() 2Oh+'0`   ( 4@HPX1ssnassfassassNormalOEM3MMicrosoft Word 10.0@V@x,@JSummaryInformation(DocumentSummaryInformation8!CompObjdj՜.+,0 hp  mankind Y 1 Title@@@ NormalCJ_HaJmH sH tH DA@D Default Paragraph FontRi@R  Table Normal4 l4a (k@(No List^O^ %NhList Paragraphd^CJOJQJ^JaJ[>dfk7Z]000x00000000x0x000000>dfk]\>00\>0'\>00\>00\>00^>00\>00\>00\>00\>00^>0 0\>00^>00^>00   [:::8@0(  B S  ? OLE_LINK1>]c]]7]3cdhcefjj-.5667WY]]2rKf^`^Jo(.^`^J.pL^p`L^J.@ ^@ `^J.^`^J.L^`L^J.^`^J.^`^J.PL^P`L^J.2rK           XM?e%Nh?oR0qdhL_;B@66dee664[P@P P@PUnknownGz Times New Roman5Symbol3& z ArialU.{ @CalibriCentury Gothic5Mangal"hrRzR  !24YY3Q H)?XM1nassOEM   FMicrosoft Word Document MSWordDocWord.Document.89q