Quantcast

A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

radh

  • 2 years ago

Statistics help?

  • This Question is Closed
  1. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Grades can be converted into numbers (as in calculating a GPA) where an A = 4, B = 3, C = 2, D = 1, and F = 0. For a fictional class, the grade distribution was: X(Grade) 4 3 2 1 0 P(X) 0.20 0.25 0.30 0.10 0.15 a) Verify that this is a legitimate probability distribution. b) Find the mean grade for this class. c) Find the standard deviation

  2. lilfayfay
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    wrong section

  3. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    openstudy has a stats section?

  4. hartnn
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    could u do part a) ?

  5. lilfayfay
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yeah

  6. lilfayfay
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    at the top it will say "Find More Subjects"

  7. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yeah, I know part a. It's legitimate because the total probability is equal to 1.

  8. hartnn
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    good, thats correct. where r u stuck ?

  9. lilfayfay
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Yeah its at the very bottom if you click on "Find More Subjects" at the top :))

  10. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    finding the mean/sd. i found those out, but idk how to corrleate them with the grades. i know mean is .2, so would that mean the average grade is 4 because its' probability is .2?

  11. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    oh, whoops. i didn't see that before. i'll go there next time.

  12. hartnn
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    mean is 0.2 ? which formula did u use ?

  13. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    total is 1, divided by 5, .2? did i do that wrong?

  14. hartnn
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yes... Mean = \(\sum xP(x)\) so, it will be mean = 0.2*4 + 0.25*3 + ......

  15. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    oooh. okay. one sec. let me calculate that. :P

  16. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    2.25?

  17. hartnn
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    don't u have answers to verify ?

  18. hartnn
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yeah, even i get 2.25

  19. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    nope. answers are given upon completion. :P

  20. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    but thanks, I think I got it now. Wrong formula. :P

  21. hartnn
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    and u know formula for sd ?

  22. radh
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yeah, got that. i compared that with a friend, and she got the same answer. it was just the mean.

  23. hartnn
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    ok, good :)

  24. hanban1
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    hartnn, if you don't mind could you explain how to find the standar deviation, i'm a bit confused on how to go about it.

  25. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.