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It is worth noting that it is only the product of two odd numbers which results into an old number. If the number of odd integers in the sample is three, say, X, Y and Z, then their possible products are XY, XZ and YZ. This means that the total number of integers in the sample is 5.
Hence if 1/5=3, 1=3*5/1=15 possible outcomes (products). This means that the number of integers is 5 since five integers have 15 possible product outcomes.
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