1\frac{1}{2}+\frac{1}{4}+\frac{1}{12}+\frac{1}{20}+\frac{1}{10}+1\frac{2}{3}=1\frac{30}{60}+\frac{15}{60}+\frac{5}{60}+\frac{3}{60}+\frac{6}{60}+1\frac{40}{60}=2\frac{70}{60}+\frac{29}{60}=
=3\frac{10}{60}+\frac{29}{60}=3\frac{39}{60}=3\frac{13}{20}
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3\frac{13}{20}:3=\frac{73}{20}*\frac{1}{3}=\frac{73}{60}=1\frac{13}{60}(kg)\approx1,22kg <-- odpowiedź