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Cześć!
Poziom A
[tex]7\frac{1}{3}+(-6\frac{2}{3})=7\frac{1}{3}-6\frac{2}{3}=6\frac{4}{3}-6\frac{2}{3}=\frac{2}{3}\\\\-5,11+(-3,45)=-(5,11+3,45)=-8,56\\\\-2\frac{5}{6}+(-1\frac{5}{6})=-(2\frac{5}{6}+1\frac{5}{6})=-3\frac{10}{6}=-3\frac{5}{3}=-4\frac{2}{3}\\\\4,2+(-7,8)=4,2-7,8=-(7,8-4,2)=-3,6[/tex]
Poziom B
[tex]8\frac{1}{3}-(-4\frac{2}{3})=8\frac{1}{3}+4\frac{2}{3}=12\frac{3}{3}=13\\\\-5,11-3,45=-(5,11+3,45)=-8,56\\\\2\frac{5}{6}-7\frac{5}{6}=-(7\frac{5}{6}-2\frac{5}{6})=-5\\\\-4,2-(-7,8)=-4,2+7,8=7,8-4,2=3,6[/tex]
i) [tex]7\frac{1}{3} +(-6\frac{2}{3})=\frac{22}{3} -\frac{20}{3} =\frac{2}{3}[/tex]
j) [tex]-5,11 + (-3,45)= -8,56[/tex]
k) [tex]-2\frac{5}{6} +(-1\frac{5}{6} )=-3\frac{10}{6} =-4\frac{4}{6}=-4\frac{2}{3}[/tex]
l) [tex]4,2+(-7,8)=4\frac{2}{10} -7\frac{8}{10} =\frac{42}{10}-\frac{78}{10} =-\frac{36}{10}=-3\frac{6}{10}[/tex]
i) [tex]8\frac{1}{3} -(-4\frac{2}{3} )=8\frac{1}{3} +4\frac{2}{3} =13\\[/tex]
j) [tex]-5,11 + (-3,45)= -8,56[/tex]
k) [tex]2\frac{5}{6} -7\frac{5}{6} =-5[/tex]
l) [tex]-4.2-(-7,8)=-4\frac{2}{10} +7\frac{8}{10} =-\frac{42}{10}+\frac{78}{10} =\frac{36}{10} =3\frac{6}{10}[/tex]