I am a two-digit number. If you reverse my digits, I become 9 less than what I was. What number am I?
Category: Math · Difficulty: medium
Hint: Think about how you can manipulate digits.
Answer
54
Explanation
Let the number be 10a + b. Reversing gives 10b + a, and 10b + a = 10a + b - 9 leads to the solution.
This is a medium math riddle — a moderate challenge for most people. The answer is 54.
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