Question

(Adapted from Tolga Tasdizen): We have a bag with 5 red marbles and 9 blue marbles. You draw three marbles out of the bag without replacement.

(a) What is the probability that you got a red, blue, and red marble in that order? Hint: use the multiplication rule to get the size of the sample space (and size of the event set) as if the marbles were distinguishable.

(b) What is the probability of not getting any blue marbles?

(c) What is the probability you got two red and one blue marble, in any order? Hint: add the numbers of each ordering of getting two reds and one blue marble.

ue marbles. You draw three marbles out of the bag without replacement. a) What is the probability that you got a red, blue, and red marble in that order? Hint: use the multiplication rule to get the size of the sample space (and size of the event set) as if the marbles were distinguishable (b) What is the probability of not getting any blue marbles? (c) What is the p add the numbers of each ordering of getting two reds and one blue marble.

Answer 1

A There are 5 red marbles and 9 blue marbles in a bag therefore bag contain g + 5 = 19 marbles We draw 3 marbles without replacement, the number of ways this can be happen is RRR, RRb, RBR, BRR, BBB,BBR, BRB, RBB this means there are 8 different ways a) P(RBR) = 8P_3/14P_3 = 336/2189 P(RBR) = 0.1538 R - Red, B - Blue \r\n There is only one possible way which is not getting blue therefore P(Not getting blue) = P(RRR) = 8P_1/14P_3 = 8/2184 c) There are 3 different ways target 2 red and 1 blue marble therefore probability that getting 2 red and 1 blue marble is P = 8P_3/14P_3 = 336/2184 = 0.1538