To identify the composite number based on the given criteria, let's analyze the clues step by step:
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Composite Number: A composite number has more than two factors, meaning it can be divided evenly by numbers other than 1 and itself.
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Range: The number must be greater than 16 and less than 20. The whole numbers in this range are 17, 18, and 19.
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Factors: The clue states that two of the number's factors are a number \( n \) and \( n \) doubled (which is \( 2n \)). For these to be factors of the composite number, the number must be able to be expressed as \( n \times m \) where \( n \) and \( 2n \) are both factors.
Now let's analyze the numbers between 17 and 20:
- 17: This is a prime number, so it cannot be composite.
- 18: The factors of 18 are 1, 2, 3, 6, 9, 18. We can see that 2 (which is \( n \)) and 4 (which is \( 2n \)) fit here, as \( n = 2 \) leads to \( 2n = 4\), but since 4 is not a factor of 18, we cannot conclude.
- 19: This is a prime number, hence, it cannot be composite.
From this analysis, the only number that fits all conditions is 18.
Thus, the composite number you are referring to is 18.