1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Simple Probability Question

Tags:
  1. Sep 24, 2015 #1
    Hey, I am new to this forum and I wanted to ask on something important for my work concerned with sociology.

    I believe I know this but I am just making sure.

    Let's say you don't know what a person is going to do next, but you do know it's between 3 options: A, B and C.
    Do we say, in this case, that there's a 33% for each to occur?
    Moreover, A and B always lead to one result Y.
    Hence, Y has a 66% to occur?

    That's it! I know it's very simple but I just have to get this off my head, I am not really sure this is the right section to place it though.

    Thanks.
     
  2. jcsd
  3. Sep 24, 2015 #2

    Orodruin

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    No, you cannot say this in general unless you have some additional information such as it being equally likely for the person to pick each of the alternatives. For example, in the cafeteria at my institute there are always three options for lunch, one meat dish, one fish dish, and one vegetarian. The probability that I pick the meat dish on any given day is of the order of 98%.
     
  4. Sep 24, 2015 #3
    What if you don't have any information to prove that one is more likely than the other? Does that render this unsolvable?
     
  5. Sep 24, 2015 #4

    Orodruin

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    Yes, in order to solve it you need to be supplied with the information that the alternatives are equally likely (or if not, what their probabilities are).
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Simple Probability Question
  1. Probability question (Replies: 4)

  2. Probability Question (Replies: 8)

  3. Probability Question (Replies: 4)

  4. Probability Question (Replies: 2)

Loading...