Answer:
Step-by-step explanation:
Given the 3 sets of balls numbered 1 through 12, the total number of balls:
12 * 3 = 36 balls.
The balls have the same numbers if they are on the:
1, 1, 1
2, 2, 2
3, 3, 3
and so on.
This can happen 12 times.
Finally, the probabiliticy we seek is
12/(36C3)
36C3 = 36!/(36 - 34)!3!/(36C3)
36C3 = 36!/(36 - 34)!3!
12