statistics help required

Oct 16th, 2014
RockCafe
Category:
Statistics
Price: $15 USD

Question description

You can take 30 minutes

Question 1

  1. What requirements are necessary for a normal probability distribution to be a standard normal probability distribution?

    a.

    The mean is 1 and the standard deviation is 0.

    b.

    The mean is 0 and the standard deviation is 0.

    c.

    The mean is 0 and the standard deviation is 1.

    d.

    The mean is 1 and the standard deviation is 1.

1 points  

Question 2

  1. The area under the standard normal curve to the left of z = 1.34 is Blank 1 . (Round to four decimal places)

2 points  

Question 3

  1. The area under the standard normal curve to the right of z = -0.65 is Blank 1 . (Round to four decimal places)

2 points  

Question 4

  1. The area under the standard normal curve between z = -2.29 and z = -1.22 is Blank 1 . (Round to four decimal places)

2 points  

Question 5

  1. IQ scores for adults are normally distributed with a mean of 100 and a standard deviation of 15.  If an adult is chosen at random, what is the probability their IQ score is less than 90? (Change to z-score and use standard normal table.)

    a.

    0.2514

    b.

    0.9525

    c.

    0.0475

    d.

    0.7486

1 points  

Question 6

  1. A safety light is designed so that the times between flashes are normally distributed with a mean of 3.50 seconds and a standard deviation of 0.50 seconds.  Find the probability that an individual time is greater than 4.50 seconds.

    a.

    0.0228

    b.

    0.9821

    c.

    0.1587

    d.

    0.9772

1 points  

Question 7

  1. Women's heights are normally distributed with a mean of 63.5 inches and a standard deviation of 2.5 inches.  What percentage of women are between 62 and 70 inches tall?  Blank 1 %  (Round to one decimal place)

2 points  

Question 8

  1. Find the z-scores for which 80% of the standard normal distribution's area lies between -z and z.

    a.

    z = -1.28 and z = 1.28

    b.

    z = - 1.96 and z = 1.96

    c.

    z = - 0.84 and z = 0.84

    d.

    z = -2.33 and z = 2.33

1 points  

Question 9

  1. Two high school students took equivalent language tests, one in German and one in French.  The student taking the German test, for which the mean was 66 and the standard deviation was 8, scored an 82, while the student taking the French test, for which the mean was 27 and the standard deviation was 5, scored a 35.  Use z-scores to compare the scores.

    a.

    A score of 82 with a mean of 66 and a standard deviation of 8 is better.

    b.

    The two scores are statistically the same.

    c.

    You cannot determine which score is better from the given information.

    d.

    A score of 35 with a mean of 27 and a standard deviation of 5 is better.

1 points  

Question 10

  1. The scores on a mathematics exam have a mean of 74 and a standard deviation of 8.  What is the score that corresponds to the 30th percentile?  Blank 1   (Round to two decimal places)

2 points  

Question 11

  1. Assume that blood pressure readings are normally distributed with a mean of 117 and a standard deviation of 5.  A researcher wishes to select people for a study but wants to exclude the top 10%.  What would be the largest reading that would still qualify the person for the study?

    a.

    110.6

    b.

    123.4

    c.

    122.4

    d.

    132.9

1 points  

Question 12

  1. Assume that human body temperatures are normally distributed with a mean of 98.21º F and a standard deviation of 0.61º F.  Find the temperature at the third quartile.  This means 75% of the temperatures are below this point.

    Blank 1 º F  (Round to two decimal places)

2 points  

Question 13

  1. Men's heights are normally distributed with a mean of 69.0 inches and a standard deviation of 2.8 inches.  The U.S. Marine Corps requires that men have heights between 64 inches and 78 inches.  Find the percentage of men that meet this requirement.  Blank 1 %  (Round to two decimal places)


Tutor Answer

(Top Tutor) Daniel C.
(997)
School: UT Austin
PREMIUM TUTOR

Studypool has helped 1,244,100 students

3 Reviews


Summary
Quality
Communication
On Time
Value
BlueOcean
Nov 15th, 2016
" Awesome! Exactly what I wanted. "
ashleyisgod
Oct 24th, 2016
" Top quality work from this guy! I'll be back! "
Molly_Moon
Oct 1st, 2016
" AMAZING as always! "
Ask your homework questions. Receive quality answers!

Type your question here (or upload an image)

1822 tutors are online

Brown University





1271 Tutors

California Institute of Technology




2131 Tutors

Carnegie Mellon University




982 Tutors

Columbia University





1256 Tutors

Dartmouth University





2113 Tutors

Emory University





2279 Tutors

Harvard University





599 Tutors

Massachusetts Institute of Technology



2319 Tutors

New York University





1645 Tutors

Notre Dam University





1911 Tutors

Oklahoma University





2122 Tutors

Pennsylvania State University





932 Tutors

Princeton University





1211 Tutors

Stanford University





983 Tutors

University of California





1282 Tutors

Oxford University





123 Tutors

Yale University





2325 Tutors