Matt has a bag containing 12 green marbles and 8 blue marbles. Without looking, he pulls out one marbles and places it on the table. He then picks a second marbles from the bag. What is the probability he will have 2 blue marbles?

Answer 1

Probability= action×action

P= 8/20 × 7/19 (because one blue is gone)
P= 56/380
P= 14/95