6 7 8 9 10 11 12 13 118 87 116 75 96 122 103 116 170 103 145 78 107 84 148 147 19 20 21 22 23 24 25 6.12 to 20.58 O 5.47 to 21.17 O 6.26 to 20.44 O 5.12 to 21.52 111 89 78 100 89 85 88 112 93 76 116 78 101 123 To access the complete data set, click the link for your preferred software format: Excel Minitab JMP SPSS TI R Mac-TXT PC-TXT CSV CrunchIt! Give a 90% confidence interval for the mean time advantage of right-hand over left-hand threads