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Look! It's A Rectangle!

Geometry Level 1

\[ \Large 12 \times 1^2 + 6 \times 2^2 + 4 \times3^2 + 3\times4^2 = \, ? \]

\[1\times2\times3\times4\times5\times6\] \[1\times2\times3\times4\times5\] \[1\times2\times3\times4\times5\times6\times7\] \[1\times2\times3\times4\]

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by Chung Kevin

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