Probability question for Stats class help.

Question

Suppose that we have  15 marbles in a jar. 7 of them are green, 2 of them are blue, and the rest are red.

 

1)What is the probability that the first marble we draw is blue?
2)Suppose you drew a blue marble on the first draw. If drawing with replacement, what is the probability of drawing a red marble?
3)If drawing with replacement, what is the probability of drawing two green marbles in a row?
4)If drawing without replacement, what is the probability that the first three marbles we draw are all red?
5)Is drawing a red and green marble independent events? Are they disjoint?

 

Is it possible showing step by step by with answering these questions?

 

 

 

 

 

 

Answer 1

Pr(B) = 2/15

Pr(R) = 6/15 = 2/5 = 0.4

Pr(2G) = 7/15 x 7/15 = 49/225

Pr(3R) = 9/15 x 8/14 x 7/13 = 3/5 x4 x 1/13 =12/65