iran-konkur 2021 Q132

iran-konkur · Other · konkur-riazi_1400_specialized Number Theory Divisibility and Divisor Analysis
132- The number of positive multiples of positive integer $x = 3^m \times 5^n$ that are also multiples of positive integer $\dfrac{x}{40}$ is more than 12. What is the minimum value of $x$?
(1) $640$ (2) $800$ (3) $1000$ (4) $1280$
\textbf{132-} The number of positive multiples of positive integer $x = 3^m \times 5^n$ that are also multiples of positive integer $\dfrac{x}{40}$ is more than 12. What is the minimum value of $x$?

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(1) $640$ \hfill (2) $800$ \hfill (3) $1000$ \hfill (4) $1280$

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