If there are 6 red marbles, 6 white marbles, and 4 blue marbles, then there are 16 marbles total. To find the probability (P) of either the red or blue marbles, you will add together the number of red and blue marbles, and divide that by the total:
(6 + 4) / (6 + 6 + 4) 10/14
This fraction can further reduce to 5/8 (by dividing both the numbers by 2).
