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  • A number added to twice itself gives twenty-one. Find tha...
Multiple choice general knowledge math & puzzles

A number added to twice itself gives twenty-one. Find that number!

  1. 5

  2. 6

  3. 7

  4. 9

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let the number be x. Then x + 2x = 21, which simplifies to 3x = 21. Therefore x = 7. Option C (7) is correct.

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