Our compound has 1 mole Fe for every 1.5 moles O. 1 is a whole number, but 1.5 is not. We need to multiply both 1 and 1.5 by some number such that the product will be whole numbers such as 2, 3, 4, etc.

What is the smallest number that when multiplied by 1 and 1.5 will change both of them into whole numbers?

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