This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: Suppose z is the standard normal random variable. Use Excel to calculate the following: a. P(z ... (Read 43 times)

frankwu

  • Hero Member
  • *****
  • Posts: 549
on: Jun 24, 2018
Suppose z is the standard normal random variable. Use Excel to calculate the following:
 a. P(z  2.5)
  b. P(0  z  2.5)
  c. P(2  z  2)
  d. P(z  0.38)
  e. P(z  1.62)
  f. z value with 0.05 in the lower tail
  g. z value with 0.05 in the upper tail

Question 2

Fifty students are enrolled in an Economics class. After the first examination, a random sample of five papers was selected. The grades were 60, 75, 80, 70, and 90.
 a. Calculate the estimate of the standard error of the mean.
  b. What assumption must be made before we can determine an interval for the mean grade of all the students in the class? Explain why.
  c. Assume the assumption of part (b) is met. Provide a 90 confidence interval for the mean grade of all the students in the class.
  d. If there were 200 students in the class, what would be the 90 confidence interval for the mean grade of all the students in the class?


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

ciecieme

  • Sr. Member
  • ****
  • Posts: 331
Reply #1 on: Jun 24, 2018
Answer to Question 1

a. P(z  2.5) =NORM.S.DIST(2.5,TRUE)
b. P(0  z  2.5) =NORM.S.DIST(2.5,TRUE)-NORM.S.DIST(0,TRUE)
c. P(2  z  2) =NORM.S.DIST(2,TRUE)-NORM.S.DIST(-2,TRUE)
d. P(z  0.38) =NORM.S.DIST(-0.38,TRUE)
e. P(z  1.62) =1-NORM.S.DIST(1.62,TRUE)
f. z value with 0.05 in the lower tail =NORM.S.INV(0.05)
g. z value with 0.05 in the upper tail =NORM.S.INV(0.95)

Answer to Question 2

a. 4.79
b. Since the sample is small (n < 30) and  is estimated from s, we must assume the distribution of all the grades is normal.
c. 64.783 to 85.217
d. 64.34 to 85.66


frankwu

  • Member
  • Posts: 549
Reply 2 on: Jun 24, 2018
YES! Correct, THANKS for helping me on my review

Mochi

  • Member
  • Posts: 300
Reply 3 on: Yesterday
Thanks for the timely response, appreciate it

« previous next »
 

Did you know?

Many of the drugs used by neuroscientists are derived from toxic plants and venomous animals (such as snakes, spiders, snails, and puffer fish).

Did you know?

Every flu season is different, and even healthy people can get extremely sick from the flu, as well as spread it to others. The flu season can begin as early as October and last as late as May. Every person over six months of age should get an annual flu vaccine. The vaccine cannot cause you to get influenza, but in some seasons, may not be completely able to prevent you from acquiring influenza due to changes in causative viruses. The viruses in the flu shot are killed—there is no way they can give you the flu. Minor side effects include soreness, redness, or swelling where the shot was given. It is possible to develop a slight fever, and body aches, but these are simply signs that the body is responding to the vaccine and making itself ready to fight off the influenza virus should you come in contact with it.

Did you know?

The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.

Did you know?

According to the American College of Allergy, Asthma & Immunology, more than 50 million Americans have some kind of food allergy. Food allergies affect between 4 and 6% of children, and 4% of adults, according to the CDC. The most common food allergies include shellfish, peanuts, walnuts, fish, eggs, milk, and soy.

Did you know?

The first war in which wide-scale use of anesthetics occurred was the Civil War, and 80% of all wounds were in the extremities.

Pediatric Vital Signs Normal Ranges Pediatric Vital Signs Normal Ranges
Standard Medical Record and Types of Reports Found in Record Standard Medical Record and Types of Reports Found in Record
The normal food link between sea urchins and algae/ Corals The normal food link between sea urchins and algae/ Corals
Suppose that we have a sample space with five equally likely experimental outcomes: E1, E2, E3, ... Suppose that we have a sample space with five equally likely experimental outcomes: E1, E2, E3, ...
In 2000, the average charge of tax preparation was 95 . Assuming a normal distribution and a ... In 2000, the average charge of tax preparation was 95 . Assuming a normal distribution and a ...
Random distribution of dandelions Random distribution of dandelions
Video: Hierarchical Sequencing Method - Sequence Tagged Sites

For a complete list of videos, visit our video library