Question

There is a bag filled with 3 blue and 5 red marbles. A marble is taken at random from the bag, the colour is noted and then it is not replaced. Another marble is taken at random. What is the probability of getting exactly one blue

Answer 1

probability of picking blue first and red later,

p(br) = 3/8 × 5/7 = 15/56

probability of picking first red and blue next is,

p(rb) = 5/8 × 3/7 = 15/56

probability of getting exactly one blue marble

=p(rb) + p(br)

= 15/56 + 15/56 = 30/56 = 15/ 28

Answer 2

Answer:

probability for exactly one blue marble

total number of marbles=

3blue + 5red= 8marbles

numer of Blue marble=3

probability=3/8

probability in %=

3/8×100=37.5%