Difference of two numbers is minimum when they are close to each other as much as possible. So I think 234-165=69 (C)
To make sure that we have arrived the minimum difference, we can look through the answer choices. In our case we should only look at the options lower than 69: D)60 and E)47.
D) 60 - cannot be the answer, because in order units digit to be 0, the two three-digit numbers' units digit must be the same which is not allowed in this question or both of them must be 0, which is not included in this range (since we deal with only
positive integers here, 0 is neither positive nor negative) as well. Hence, D is off.
E) 47- only case when the units digit of the difference of these two numbers is 7, is ab3-cd6. In all such cases the answer is more than 47. E is off as well.
So answer is C-69
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