# statistics

A bag contains 7 red marbles, 6 white marbles, and 10 blue marbles. You draw 4 marbles out at random, without replacement. What is the probability that all the marbles are red?

What is the probability that exactly two of the marbles are red?

What is the probability that none of the marbles are red?

1. 👍 0
2. 👎 0
3. 👁 105
1. prob(probability that all the marbles are red)
= (7/23)(6/22)(5/21)(4/20) = 1/253

or, by combinations:
prob(all 4 red) = C(7,4) / C(23,4) = 35/8855 = 1/253

b) probability that exactly two of the marbles are red
= C(7,2)*C(16,2) / C(23,4) = 21*120/8855 = 72/253

c) probability that none of the marbles are red ---> implies they are either white or blue
= C(16,4) / C(23,4) = ...

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Math

A bag contains 6 red marbles, 3 white marbles, and 7 blue marbles. You pick a marble without looking. Find the probability of drawing a white marble. Can someone please explain how I would work this out?

asked by Emily on May 21, 2018
2. ### math check probability

5. A bag contains 7 green marbles and 4 white marbles. You select a marble at random. What are the odds in favor of picking a green marble? A. 7:11**? B. 7:4 C. 4:7 D. 3:7 ------------------------------------ 6. Food Express is

asked by k.k on May 4, 2014
3. ### Probability

jeff has 8 red marbles, 6 blue marbles, and 4 green marbles that are the same size and shape. he puts the marbles into a bag, mixes the marbles, and randomly picks one marble. what is the probability that the marble will be blue?

asked by Jay on April 24, 2016
4. ### Math

A bag contains 5 green marbles, 8 red marbles, 11 orange marbles, 7 brown marbles, and 12 blue marbles. you choose a marble, replace it, and choose again. what is P(red then blue.)

asked by SchoolHelpNeeded on May 7, 2014
5. ### Math

A bag contains 6 red marbles, 3 white marbles , and 7 blue marbles. you pick a marble without looking. find the probability of drawing a white marble.

asked by Roblox-levelalexthegreatest on May 21, 2018
1. ### math

A bag contains 8 red marbles, 5 blue marbles, 8 yellow marbles, and 6 green marbles. What is the probability of choosing a red marble if a single choice is made from the bag? is it 8/27 ?

asked by bev on February 25, 2018
2. ### math

a bag contains 7 green marbles, 9 red marbles, 10 orange marbles, 5 brown marbles, and 10 blue marbles. you choose a marble, replace it, and choose again. what is P(read, then blue)? A. 77/164 B. 19/41 C. 90/1681 D. 45/41

3. ### Probability!

A bag contains 5 green marbles , 8 red marbles, 11 orange marbles, 7 brown marbles, and 12 blue marbles. You choose a marbles, replace it, and choose again. what is p(red then blue) 20/43 40/43 20/1849 96/1849

asked by InDireNeedOfHelp on June 9, 2014
4. ### Math geometry

Please help , I only need the second part of the question Betty picks 4 random marbles from a bag containing 3 white , 4 yellow and 5 blue marbles The probability that exactly 1 of the 4 marbles drawn is blue is (0.3535) . The

asked by Katy on May 2, 2017
5. ### Math-Algebra 1

You have a bag which contains only red and green marbles. In this bag with x^2+5 marbles total, x+1 are red. Also, x-3 marbles have a scratch on them. The probability of drawing a red marble from the original bag is equal to that

asked by Jalaia on September 13, 2017