Question 1000962
The dice have 36 outcomes.
6 of them are the same: 1,1;2,2;3,3;4,4;5,5;6,6
the other 30 are not.
For 3 dice, there are 216 outcomes.
at least two means two or three are the same.
three occurs 36 in 216 times.  That is (1/6)(1/6)(1/6)*6 for each number (1/6)-111,222,333,444,555,666
Suppose the first die is a 1: two occur (1/6)(1/6)(5/6)*3, because there are 3 ways the two can occur.
That is 15/216.  But that can occur for each of the six numbers.  The probability is 90/216 that exactly two will occur, and the probability 96/216, or 6/13.
111 
112
113
114
115
116
121
122
123
124
125
126
131
132
133
134
135
136
141
142
143
144
145
146
151
152
153
154
155
156
161
162
163
164
165
166