I did this problem but my figures were still wrong.

. . . M l_J i 0 H inewconnectmheducatinnaom 0| m - Ell Wk 4 - Practice: Wk 4 Exercises [due Sat] 0 58M Help Save 5 Exit Submit Check my work mode : This shows what is correct or incurred for the work you have completed so far. It does not indicate completion. Return to question ; A special bumper was installed on selected vehicles in a large fleet. The dollar cost of body repairs was recorded for all vehicles that were involved in accidents over a 1-year period. Those with the special bumper are the test group and the other vehicles are the control group, shown below. Each \"repair incident" is dened as an invoice (which might include more than one separate type of 2 damage). palms Statistic Test Group Control Group Mean Damage X1 = 5 1.249 X2 = ii 1.79 Samp'le Std. Dev. 51 = s 671' 52 = $ 809 Repair Incidents "1 = 15 "2 = 12 Source: Unpublished study by Thomas W. Lauer and Floyd 6. Willoughby. (a) Construct a 90 percent confidence interval for the true difference ofthe means assuming equal variances. [Round your nal answers to 3 decimal places. Negative values should be Indicated by a minus sign.) The 90% condence interval is from 4243.701 0 to 36.299 0 (bl Repeat part (a), using the assumption of unequal variances with Welch's formula for alt (Round the calculation for Welch's dfto the nearest integer. Round your final answers to 3 decimal places. Negative values should be indicated by a minus sign.) The 90%condence interval is from 4263.183 Oto 1.81? a (c) Did the assumption about variances change the conclusion? ' Yes Safari File Edit View History Bookmarks Window Help 28 97% 27 Wed May 20 4:59 AM Q E ... G newconnect.mheducation.com C mask facemas... Walmart.com |... eCampus: Home Content Connect - Clas.. Help - Q&A fro. MHE Reader Wk 4 - Practic.. Solved: A speci.. Market | Your. Advertisers Fe.. Desmos | Scien. + Wk 4 - Practice: Wk 4 Exercises [due Sat] i Saved Help Save & Exit Submit Check my work mode : This shows what is correct or incorrect for the work you have completed so far. It does not indicate completion. Return to question 7 al ISVCIS W 3 UCLIIIIal PIGLES. IVEyaLIVE Values SI lulu UE II luILalu wy a IIIIIIu> >IyII.) The 90% confidence interval is from -1243.701 * to -86.299 2 (b) Repeat part (a), using the assumption of unequal variances with Welch's formula for d.f. (Round the calculation for Welch's df to the points nearest integer. Round your final answers to 3 decimal places. Negative values should be indicated by a minus sign.) The 90% confidence interval is from -1268.183 @ to -61.817 (c) Did the assumption about variances change the conclusion? O Yes No (d) Construct separate 90% confidence intervals for each mean. (Round your intermediate tcrit value to 3 decimal places. Round your final answers to 2 decimal places.) Mean Damage Confidence Interval X1 = $1,249 ($ 740. 151 x , $ 1246.44 ( ) X2 = $1,790 ($ 1461.849 x , $ 2285.56 E. HH Graw 7 of 15 Education tv O! MAY W X O 20