154- Six numbered balls are randomly placed in 3 boxes. What is the probability that no box remains empty? (1) $\dfrac{5}{14}$ (2) $\dfrac{5}{12}$ (3) $\dfrac{3}{7}$ (4) $\dfrac{7}{12}$
\textbf{154-} Six numbered balls are randomly placed in 3 boxes. What is the probability that no box remains empty?
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(1) $\dfrac{5}{14}$ \hfill (2) $\dfrac{5}{12}$ \hfill (3) $\dfrac{3}{7}$ \hfill (4) $\dfrac{7}{12}$
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