15.6.24 Definition and properties of probability

Condition: There are 10 balls in the box: 2 white, 5 green and 3 red. 3 balls are drawn at random. Find the probability of the following events: a) 3 balls are green; b) 1 red, 2 white; c) 2 green, 1 white; d) all the balls are different colors.