A bag contains 10 red marbles, 3 blue marbles, 7 white marbles, and 5 green marbles. find the probability of picking one of each four colours in the first tries without the marbles being replaced.

10/25 red marble x 3/24 blue marble x 7/23 white marble x 5/22 green marble =1,050/303,600 =0.0034585 x 100 =o.34585% - probability of picking one of each colors on the first try.