Question

alice has a box that contains 12 marbles consisting of 4 green ones 4 yellow ones and 4 blue ones. if alice was in a dark room and she had to pick them at random how many marbles must she take out so as to pick out at least 2 of one color?

Answer 1

The probability of getting at least two marbles of same color :

Yellow :

2/12 or 3/12 or 4/12

1/6 + 1/4 + 1/3 = 9/12

Blue :

2/12 or 3/12 or 4/12

9/12

Green:

2/12 or 3/12 or 4/12

9/12

3/4 × 3/4 × 3/4 = 27/64

27/64 × 12 = 5 1/16

Taking the whole part :

We have five.