Add me to myself and get eighteen, subtract me from itself and get zero. What number am I?
Category: Math · Difficulty: easy
Hint: Think of a number that when doubled gives eighteen.
Answer
A number nine exactly
Explanation
Nine doubled is eighteen, and the number minus itself is zero, meeting the conditions.
This is an easy math riddle — a good one for children and beginners. The answer is A number nine exactly.
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