Post a New Question

pre-calculus

posted by .

An urn contains 7 red marbles labeled (1,2,3,4,5,6,7) and 5 green marbles labeled (1,2,3,4,5) four marbles are pulled out at once. what is the probability.

A. all four marbles are red

B. more of the marbles are green than red

C. both red and green marbles are present

D. two of the marbles chosen are both labeled 5

  • pre-calculus -

    A) prob (4reds) = (7/12)(6/11)(5/10)(4/9) = 7/99
    or
    Prob = C(7,4)/C(12,4) = 35/495 = 7/99

    B) could be GGGG, GGGR
    Prob = C(5,4)/C(12,4) + C(5,3)*C(7,1)/C(12,4
    = 5/495 + 70/495 = 75/495 = 5/33

    C) can't have all red or all green
    prob = 1 - (all red + all green)
    number of all green = C(5,4) = 5
    so prob = 1 - (7/99 + 5/495) = 91/99

    D) both are labelled 5
    prob = C(2,2)*C(10,2)/C(10,4) = 45/495 = 1/11

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Probability

    An urn contains 7 red marbles labeled {1,2,3,4,5,6,7} and 5 green marbles labeled {1,2,3,4,5}. Four marbles are pulled out at once. What is the probability that A. All four marbles are red?
  2. Algebra

    Out of jar with 100 marbles, 49 are blue marbles, 7 are green marbles, 27 are red marbles and 17 are yellow marbles. What is the probability of drawing a red marble?
  3. probability problem

    A box contains 6 green, 8 red, 5 yellow, and 10 blue marbles. Four marbles are drawn from the box at the same time. a) What is the probability that all four marbles are the same color?
  4. Math

    A bag of marbles contains only green and red marbles. All of the marbles are the same size. If the probability of selecting a green marble is 1/2. Which is most likely to be the number of green and red marbles in the bag?
  5. Discrete Math

    A bag contains 5 red marbles, 4 yellow marbles, 3 green marbles, 2 orange marbles and 2 purple marbles. If three marbles are removed, what is the probability that at least one of them is red?
  6. math

    A bag contains 5 red marbles, 6 white marbles, and 8 blue marbles. You draw 5 marbles out at random, without replacement. What is the probability that all the marbles are red?
  7. Math

    A bag contains 9 red marbles, 8 white marbles, and 6 blue marbles. You draw 4 marbles out at random, without replacement. What is the probability that all the marbles are red?
  8. Math

    A bag contains 9 red marbles, 8 white marbles, and 6 blue marbles. You draw 4 marbles out at random, without replacement. What is the probability that all the marbles are red?
  9. math

    a bag of marbles contains 5 green marbles,4 red marbles, and six yellow marbles. What is the probability of drawing 2 yelo0w marbles with replacement
  10. Math "Need Help Asap"!

    1.)There are 35 marbles in a bag:9 blue marbles, 8 marbles, 4 red marbles, 4 red marbles, 8 white marbles, & 6 yellow marbles. Find P(Red). Write the probability as a fraction in simplest form, a decimal, & a percent. A.)4/31, 0.129, …

More Similar Questions

Post a New Question