아래 표처럼 빈칸에 수를 기록할 때 끝 셀에서 합을 해 주는 공식은 어떻게 하나요
꼭 알려주세요 ...

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<span style="background-color:rgb(204,204,204);">덧셈</span>

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2

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3

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7

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4

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16(합)

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<span style="background-color:rgb(204,204,204);">뺄셈</span>

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20

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3

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4

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1

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3

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8(차)

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