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Are you prime

Number Theory Level 1

How many of the following 10 numbers are prime?

\[ \begin{array} { l l l l l } 1, & 2 & 3 & 4 & 5, \\ 201, & 202, & 203, & 204, & 205 . \\ \end{array} \]

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Excel in math and science

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by Arron Kau

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