3.8 * 0.15 - 1.04 : 2.6 + 0.83 = 0.57 - 0.4 + 0.83 = 1.4 - 0.4 = 1
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6/13 + 4/13 - 8/13 = 10/13 - 8/13 = 2/13
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7 13/15 - ( 2 7/15 + 3 4/15 ) = 7 13/15 - 5 11/15 = 2 2/15
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13/18 + 7/12 = ( 156 + 126) / 216 = 282/216 = 141/108 = 47/36 = 1 11/36
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5/7 - 3/5 = ( 25 - 21) /35 = 4/35
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5/6 - 3/8 - 1/12 = ( 20 - 9 - 2) /24 = 9/24 = 3/8
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( 120 * 35 ) / 100 = 42 ( страницы) - занимают рисунки