Final answer:
To find the missing number in the proportion, use cross products.
Step-by-step explanation:
To find the missing number in the proportion, we can set up a cross product. The cross product of the numbers on one side of the proportion should be equal to the cross product of the numbers on the other side. In this case, 1 * 28 should be equal to X * 7. Solving for X, we have X = (1 * 28) / 7 = 4.
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