Flash3146 2ящ-x
2,4x+x+(2,4x+x)=58,48
3,4x+3,4x=58,48
6,8x=58,48:6,8
x=8,6(кг)-2 ящик
8,6*2,4=20,64(кг)-1 ящик
20,64+8,6=29,24(кг)

glebashot | x1 + x2 + x3 = 58,48 
| x2 * 2,4 = x1
| x1 + x2 = x3
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| x2 * 2,4 + x2 + x2 * 2,4 + x2 = 58,48
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| 6,8 * x2 = 58,48
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| x2 = 8,6
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| x2 = 8,6
| x1 = x2 * 2,4
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| x1 = 2,4 * 8,6 = 20,64
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| x2 = 8,6
| x1 = 20,64
| x3 = x1 + x2
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| x3 = 20,64 + 8,6 = 29,24
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Ответ: x1 = 20,64
            x2 = 8,6
            x3 = 29,24