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I was asked the question, how many numbers between 10 and 99 have digits that differ EXACTLY by 3?

I didn't understand the question, I thought it meant numbers like 11,44,77 then 22,55,88 and 33,66,99 but I was wrong. What does the question mean?

Aspiring Mathlete
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1 Answers1

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I would interpret it as meaning that the two digits of the number differ by $3$. (The absolute value of the difference between the first digit and the second digit is $3$.) Examples: $41$, $30$, $58$.

André Nicolas
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