Answer:
2/35
Step-by-step explanation:
The only way we can solve this problem is to assume that the given complement of pieces is of a full kit before one went missing. The total number of pieces in the kit is ...
... 9 + 8 + 12 + 6 = 35
Of those, 2 are red with four holes. Thus the probability that a randomly chosen piece is red with 4 holes is 2 out of 35, or 2/35.
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If this is the kit contents after the piece went missing, we have no way of knowing the color or hole count of the missing piece. If the kit is supposed to contain 13 blue pieces, for example, then the probability is zero that the missing piece is red.
