I am a number whose digital root is 9. What could I be?
Category: Math · Difficulty: expert
Hint: Think about how to calculate the digital root of numbers.
Answer
18
Explanation
The digital root is the repeated sum of digits until a single-digit number is achieved. For 18, 1 + 8 = 9.
This is a expert math riddle — one of the harder riddles here. The answer is 18.
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