153- How many non-negative integer solutions does the inequality $x + y + z \leq 5$ have? (1) $50$ (2) $54$ (3) $56$ (4) $60$
\textbf{153-} How many non-negative integer solutions does the inequality $x + y + z \leq 5$ have?
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(1) $50$ \hfill (2) $54$ \hfill (3) $56$ \hfill (4) $60$
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