Question

Пожалуйста помогите с контрольной

Answer 1

Ответ:

Пошаговое объяснение:

$1)2\frac{1}{4} +3\frac{2}{3} =2\frac{3}{12} +3\frac{8}{12}=5\frac{11}{12}\\ \\ 2)8,5-1\frac{2}{5} =8,5-1,4=7,1\\ \\ 3)5\frac{11}{12} :7,1=\frac{71}{12} :\frac{71}{10} =\frac{71}{12}*\frac{10}{71} =\frac{5}{6} \\ \\ 4)\frac{5}{6} *1,2=\frac{5}{6} *\frac{12}{10} =1\\ \\ \\ 1*35:100=0,35\\ Otvet: 0,35$

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$(x+2\frac{2}{5}):1\frac{2}{13}=8\frac{2}{3} \\ \\ x+2\frac{2}{5}=8\frac{2}{3} *1\frac{2}{13}\\ \\ x+2\frac{2}{5}=\frac{26}{3} *\frac{15}{13}\\ \\ x+2\frac{2}{5}=10\\ \\ x=10-2\frac{2}{5}\\ \\ x=7\frac{3}{5}$