Maths Olympiad Prep

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Algebra Difficulty 2.1 Junior Find the answer

If 3n=9+9+93n=9+9+9, what is the value of nn?

A number or a short expression. Spacing and $ signs are ignored.

Solution

Since 3n=9+9+9=3imes93n=9+9+9=3 imes 9, then n=9n=9. Alternatively, we could note that 9+9+9=279+9+9=27 and so 3n=273n=27 which gives n=273=9n=\frac{27}{3}=9.

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