Post a New Question


posted by .

A test is composed of six multiple choice questions where each question has 4 choices. If the answer choices for each question are equally likely, find the probability of answering 3 OR 4 questions correctly.

  • Math - probability -

    Please type your subject in the School Subject box. Any other words, including obscure abbreviations, are likely to delay responses from a teacher who knows that subject well.

  • college -

    R --- right
    W --- wrong

    so we want the case of
    RRRWWW or RRRRWW and its possible arrangements

    P(3 R) = C(6,3)(1/4^3(3/4)^3 = .131836
    P(4 R) = C(6,4)(1/4)^4(3/4)^2 = .032959

    P(3R or 4R) = the sum of those two
    = .1648

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

More Related Questions

Post a New Question