Răspuns:
2c.......3g.......= x kg
8c.......9g.......= 42 kg
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2c=3g => 9g=6c
8c........6c......= 42 kg
14c.....=42 kg
c=42kg : 14
c=3kg.are un cocoș
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8c*3kg........9g........=42kg
24kg........9g.........=42kg
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9g.........=42kg-24kg
9g........=18kg
g=18kg-9kg
g=2kg are o găină