Where are the math people? I have a question
If you have 3 six sided dice, how many rolls would you have to make (on average) before they all showed the same digit?
SW-User
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1/6^2 = 1/36
ElwoodBlues · M
@SW-User BlueVeins is correct. Look at it this way:
Your first roll doesn't matter; any number will do; probability = 1.
2nd roll needs to match the first; 1/6 probability.
3rd roll needs to match the first also, another 1/6.
1 X 1/6 X 1/6 = 1/36 answer.
Another way to look at it: consider all possible dice rolls where order of the rolls matters. 6 possibilities for each roll, so 6X6X6 = 216 possible rolls (order matters means a 3,4,5 is different from a 5,4,3). Anyway, among those 216 possible rolls, there are exactly six triples. 6/216 = 1/36 = answer.
Your first roll doesn't matter; any number will do; probability = 1.
2nd roll needs to match the first; 1/6 probability.
3rd roll needs to match the first also, another 1/6.
1 X 1/6 X 1/6 = 1/36 answer.
Another way to look at it: consider all possible dice rolls where order of the rolls matters. 6 possibilities for each roll, so 6X6X6 = 216 possible rolls (order matters means a 3,4,5 is different from a 5,4,3). Anyway, among those 216 possible rolls, there are exactly six triples. 6/216 = 1/36 = answer.