-5/8 - (-7/12) = -5/8 + 7/12 = -15/24 + 14/24 = -1/24
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38 - (-16) = 38 + 16 = 54
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- 7 7/24 - 4 13/16 = -(7 14/48 + 4 39/48) =- ( 11 53/48) = - 12 5/48
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5/9 - 2 = - (2 -5/9) = - (18/9 - 5/9) = - 13/9 = - 1 4/9
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-18.9 - 36.4 = - (18.9 + 36.4) = -55.3