Correctly predicting salt and sugar in the proper sequence. We have $10$ canisters, $5$ containing sugar and $5$ containing salt. What is the probability of naming them all in the correct order? (example: salt, sugar, sugar, salt, sugar, salt, salt, ...) 
It's different from predicting $10$ coins head or tails, because there are limited quantities of each.
Thanks.

If we assume that each arrangement of $5$ salt and $5$ sugar canisters are equally likely, then any given arrangement is uniquely determined by the placement of, say, the $5$ sugar canisters among the $10$ canisters total.  For example, we can describe one arrangement as $(2, 3, 5, 7, 10)$, meaning that the sugar canisters are found in positions $2$, $3$, $5$, $7$, $10$ (and the salt canisters are in positions $1$, $4$, $6$, $8$, $9$).  Then clearly, there are exactly $$\binom{10}{5} = 252$$ ways to select $5$ distinct numbers from the set $\{1, 2, \ldots, 10\}$, representing the positions of the sugar canisters, and since each such selection is equally likely (by assumption), the probability of randomly choosing the unique correct representation is $1/252$.
