Quantcast

Got Homework?

Connect with other students for help. It's a free community.

  • across
    MIT Grad Student
    Online now
  • laura*
    Helped 1,000 students
    Online now
  • Hero
    College Math Guru
    Online now

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

MathSofiya

More statistics. Binomial Probability \[P(r)=\frac{n!}{r!(n-r)!}p^rq^{n-r}=C_{n,r}p^rq^{n-r}\] The problem states 10% of adults deliberately do a one time fling (purchase clothing, wear 'em to an event, and return 'em). In a group of 7 adults what is the probability that anyone has done a one time fling? I figured that: n=7 r=0 I plugged those into the equation: \[P(0)=\frac{7!}{0!(7-0)!}p^0q^{7-0}=C_{7,0}p^0q^{7-0}\] What about p and q? The probability of success (p) is 0.1 (1% of people do one time flings)? and q would be 0.9? Would that be right?

  • one year ago
  • one year ago

  • This Question is Closed
  1. MathSofiya
    Best Response
    You've already chosen the best response.
    Medals 0

    @hartnn

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

    @mathslover ?

    • one year ago
  3. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    are u sure about n=7, r= 0 ?

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

    out of 7, any'one' has done a one.... so do u feel r should be 1 ?

    • one year ago
  5. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    the probability of success = probability of flinging = p = 10% = 0.1 \(\checkmark\) the probability of failure = probability of not flinging = q = 90% = 0.9 \(\checkmark\)

    • one year ago
  6. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    just clear your confusion about, n and r

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

    oh sorry I was gone for while. Let's see here. Give me a second to read everything. Sorry :S

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

    Ok so about n and r. #number of trials How do I relate that to this problem? I guessed that n=7 because it looked nice, but I don't have a good explanation for why I picked it

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

    I meant n=# of trials

    • one year ago
  10. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    number of trials or events or no. of creatures/people on which experiment is performed = n =7 here, \(\checkmark\)

    • one year ago
  11. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    r is the number of people 'chosen' here probability that anyONE has done fling implies, r=1 make sense? or more explanation?

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

    so when we say r=0...

    • one year ago
  13. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    almost never.....when we don't perform experiment.....maybe there are some special case for this

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

    make sure u understand why n=7, r=1 here

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

    When no one has done a fling wouldn't that be r=0?

    • one year ago
  16. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    umm, yes i think so....(0.9)^7 seems right

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

    a) No one has done a one-time fling? r=0 b) At least one person r=1 c.) No more than two people \[r \ge 2\] That's how I calculated it, whatcha think?

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

    b)P( atleast 1 person) =1-P (no one )

    • one year ago
  19. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    no more = less r<=2

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

    oh yes. sorry.

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

    exactly 1---->r=1 atleast 1 = 1- none

    • one year ago
  22. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    atmost 1 --> r<=1

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

    make sense ?

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

    Yes, I think so.

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

    Can I show you what I did for another problem. I think my thought process is right. Feel free to point out any errors.

    • one year ago
  26. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    i will. yes show

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

    Trevor is interested in purchasing the local hardware/sporting goods store in the small town of Dove Creek, Montana. After examining accounting records for the past several years, he found that the store has been grossing over $850 per day about 60% of the business days it is open. Estimate the probability that the store will gross over $850 (a) at least 3 out of 5 business days. (b) at least 6 out of 10 business days. (c) fewer than 5 out of 10 business days. p=.60 q=.40 a.) n=5 because "number of trials or events or no. of creatures/people on which experiment is performed " => In this case we have a total number of 5 days (events/trials) at least 3 out of 5 would mean: r>=3 To calculate this I would do P[r=3]+P[r=4]+P[r=5] b.) n=10 r>=6 To calculate.... P[r=6]+P[r=7]+P[r=8]+P[r=9]+P[r=10]

    • one year ago
  28. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    and did u get correct answer for the problem posted ? n=7,r=1,p=0.1,q=0.9

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

    and for (c) n=10 r<5

    • one year ago
  30. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    all n, r selections \(\huge \checkmark\)

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

    Yaaay!!!!! For the first problem I got a.) 0.478 b.) 0.522 c.) 0.974

    • one year ago
  32. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    sorry, i didn't do calculation part, i thought u had answers to verify, method is correct

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

    I did have the answers =)

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

    Thank you once again my friend!

    • one year ago
  35. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    so did they match? welcome ^_^

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

    yes sir!

    • one year ago
  37. hartnn
    Best Response
    You've already chosen the best response.
    Medals 2

    ok :)

    • one year ago
    • Attachments:

See more questions >>>

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.