Пожалуйста решите по действиям. Умоляю. Номер 1276.

▪1)
$(6 \frac{7}{12} - 3 \frac{17}{36} ) \times 2.5 - 4 \frac{1}{3} \div 0.65 = 1 \frac{1}{9} \\ 1) \: \: 6 \frac{7}{12} - 3 \frac{17}{36} = 6 \frac{21}{36} - 3 \frac{17}{36} = 3 \frac{4}{36} = 3 \frac{1}{9} \\ 2) \: \: 3 \frac{1}{9} \times 2.5 = \frac{28}{9} \times \frac{25}{10} = \frac{28 \times 5}{9 \times 2} = \frac{14 \times 5}{9} = \frac{70}{9} = 7 \frac{7}{9} \\ 3) \: \: 4 \frac{1}{3} \div 0.65 = \frac{13}{3} \div \frac{65}{100} = \frac{13}{3} \div \frac{13}{20} = \frac{13 \times 20}{3 \times 13} = \frac{20}{3} = 6 \frac{2}{3} \\ 4) \: \: 7 \frac{7}{9} - 6 \frac{2}{3} = 7 \frac{7}{9} - 6 \frac{6}{9} = 1 \frac{1}{9}$

▪2)
$3 \frac{3}{4} \times 1 \frac{1}{5} + (2.55 + 2.7) \div (0.1 - \frac{1}{80} ) =64.5 \\ 1) \: \: 3 \frac{3}{4} \times 1 \frac{1}{5} = \frac{15}{4} \times \frac{6}{5} = \frac{3 \times 3}{2} = \frac{9}{2} = 4 \frac{1}{2} = 4.5 \\ 2) \: \: 2.55 + 2.7 = 5.25 \\ 3) \: \: 0.1 - \frac{1}{80} = \frac{1}{10} - \frac{1}{80} = \frac{8 - 1}{80} = \frac{7}{80} \\ 4) \: \: 5.25 \div \frac{7}{80} = \frac{525}{100} \times \frac{80}{7} = \frac{21 \times 80}{4 \times 7} = \frac{3 \times 20}{1} = 60 \\ 5) \: \: 4.5 + 60 = 64.5$