This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Stat 119 Quiz 2E section 24 Name:
Red id: l. (l point)_An athlete completed an BOOm race in 140 seconds. The distribution of BOOn1 race
times foilowed a belt curve. with mean 150 seconds and standard deviation 6. The same athlete
aiso competed in a swim. finishing in 10.25 minutes. The distribution of swim times also
foilowed a beli curve, with mean 12 minutes and standard deviation 1.5 minutes. In which event
does the athlete have. a better standing relative to the other competitors in the event? A. The SOC—m race because that has the higher z~score. % W ggﬁg m g g3 mam é B The swim because that has the higher z—score f see “W “W @ The SOB—m race because that has the lower z~score é
. The swim because that has the lower z—score we 9 We .3: W is 3%»
%Ss.ii;e w f3} Answer: 2. (1 point) When the points in a normai probabiiity plot {alt along a straight tine, we infer that
the population distribution is: A. srnali B. nonwnormal C. uniform normal Answer 3. {1 point) A Z~score oi" 2 means
A. The observation is 2 standard deviations smalEer than the mean
The observation is 2 standard deviations target than the mean
. The observation is twice larger than the mean
D. The difference between the observation vaiue and the mean is 2 Answer: Use the fa owmg information to answer questions 46 Statistics exam scores foliow an approximately normal distribution with a mean of 70 points and
a standard deviation of 8 points. 4. (2 points) If a student has a Z~score of —E .5. what was the student’s actuai exam score? (show work) W E a S g: \X “36$ w t: x W Answer: 3‘ X “7.3%” ﬁlm" 5. (i point} Use the empirical rule to estimate the percentage of statistics exam scores that a
between 6?. and 94 A. 68% B. 8} 5% C. 97.5 D. 83.85% 13.95% ﬁe «i n%: m a Sp 3% é ﬁg 6. (2 points) For the distribution of statistics exam scores. what is the value of the 84Eh percentiie? Answer: 7. (3 points) In a 2002 study. the Accreditation Council t" or Graduate Medical Education found
that medical residents‘ mean number of hours worked in a week is 81.7. Suppose the number of
hours werked per week by medical residents is approximately normal. Find the standard deviation
of hours worked in a week if 4% of the medical residents work more than 90 hours per week. We Wet Answer: 5% g? Use the following information to answer problems 840
Suppose that the height of at] basketball players in National Basketbail Association is normally distributed with mean 80 inches and standard deviation of 5 inches. 8. ('3 points) What is the probability that a randomly selected player has a height of more than 82 W? e; a rim 5
§ 395%“? cram} Answer: E “3;: §* § 9. (4 points) Determine the two heights that represent the middte 90% of the distribution of
basketbail piayer heights. Knew Lse§§§§ «arse :2: Mamet” 5a,“ assertstam; seize? w W
Answer: é 3 gygé 10. (3 points) What is the. mine of the third quartiie of this distribution? X: tegeiﬁ x $§~3§ Answer: KW“ ...
View
Full
Document
This note was uploaded on 05/04/2008 for the course STAT 119 taught by Professor Helen during the Spring '07 term at San Diego State.
 Spring '07
 Helen
 Statistics

Click to edit the document details