You have 20 marbles and 20 rocks Place them into two boxes t

You have 20 marbles and 20 rocks. Place them into two boxes to increase chances of getting the marbles. Boxes are mixed up. Marbles and rocks have to be seperated for best chance to win the marbles.

Solution

SOl)

20 rocks in 1st box

20 marbles on 2nd box

Total boxes=2

Probability to choose 20 marbles box = 1/2