Question

Write the numbers 36,37,38,39,40,51,42,43 and 44in the sqaures so that each row column equal to120

Answer 1

-- I believe there's a typo in your question, and
you meant to type ' 41' instead of ' 51 '.

-- Here's how to arrange them:

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|  43  |  36  |  41  |
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|  38  |  40  |  42  |
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|  39  |  44  |  37  |
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The diagonals also add up to 120.