Question

A bag contains 5 white marbles and 5 blue marbles. You randomly select one marble from the bag and put it back. Then, you randomly select another marble from the bag. Which calculation proves that randomly selecting a white marble the first time and a blue marble the second time are two independent events?

Answer 1

1/5 this shows that each can be picked up at Least 1/5 or 2/10

Answer 2

P(A and B) =

1

2

·

1

2

Two events A and B are independent if the probability of A and B occurring together is the product of their probabilities,

P(A and B) =

1

2

·

1

2

P(red, blue) =

1

2

·

1

2

1

4

=

1

2

·

1

2