practice_prel1_sol_f08 - Engineering Statistics ENGRD2700...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Engineering Statistics ENGRD2700 Practice Prelim No.1 Solutions Fall 2008 1. (a) n = 24 + 9 + 27 = 60, Median = 1 2 ( X (30) + X (31) ) = 154 , Q 1 = 1 2 ( X (15) + X (16) = 138 , Q 3 = 1 2 ( X (45) + X (46) ) = 168 . 5 (b) IQR = 168 . 5 - 138 = 30 . 5 . 168 . 5 + 1 . 5 × 30 . 5 = 214 . 75 so 219 is an outlier on upper side. 138 - 1 . 5 × 30 . 5 = 92 . 25 so no outliers on lower side. Boxplot: Box: median line at 154, box ends at 138 and 168.5. Whisker ends at 96 and 210 (not 92.25, 214.75). Outlier at 219. (c) 90th percentile. ( i - 1 2 ) /n = 0 . 9 so i = 54 . 5. q . 9 = 1 2 ( X (54) + X (55) ) = 189 . 5 2. Note: Pr(incorrect answer) = 1 2 irrespective of whether correct answer is “true” or “false”. Pr[Pass Prelim] = ± 1 2 6 + 6 × 1 2 × ± 1 2 5 = 7 × 2 - 6 = 0 . 1094 Pr[Pass Final] = ± 1 2 10 + 10 × 1 2 × ± 1 2 9 = 11 × 2 - 10 = 0 . 01074 Pr[Pass Course] = Pr[Pass Prelim] 2 × Pr[Pass Final] = (7 × 2 - 6 ) 2 × 11 × 2 - 10 = 49 × 11 × 2 - 22 = 0 . 000129 . 3. Let A be the event that the morning lecture is bad and B that the afternoon lecture
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/26/2008 for the course ENGRD 2700 taught by Professor Staff during the Fall '05 term at Cornell University (Engineering School).

Page1 / 2

practice_prel1_sol_f08 - Engineering Statistics ENGRD2700...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online