A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

When I swing at a nail, I drive it all the way in with probability 1/2. With probability 1/4, I hit it half-way in, and with 1/4 probability I miss it entirely. Hitting it half-way in twice will drive it all of the way in. I'm pretty sure that if I swing 4 times at a nail, I'll get it all the way in almost all the time. Let's see if I'm right. How many sequences of 4 swings could leave the nail still not knocked all the way in?

  • This Question is Closed
  1. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    another question: When I swing at a nail, I drive it all the way in with probability 1/2. With probability 1/4, I hit it half-way in, and with 1/4 probability I miss it entirely. I'm pretty sure that if I swing 4 times at a nail, I'll get it all the way in almost all the time. Let's see if I'm right. What is the probability I fail to get the nail driven completely in?

  2. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    first question you could miss the nail 4 times - that's one sequence you might hit it only once in the 4 swings - that's 4 sequences that's a total of 5

  3. welshfella
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    second part probability you miss 4 times = (1/4)^4 P(hitting first time then miss next 3) = (1/4)(1/4)^3 = (1/4)^4 there are 4 different ways of doing this which gives a probability of 4*(1/4)^4 So P(failing to drive the nail in) = 5*(1/4)^4 = 5/256

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

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

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.