Question

Даю 65 балов все на скриншоте

Answer 1

Ответ:

2_4/9-3_5/6=22/9-23/6=(44-69)/18=-25/18= -1 7/18 ;

-6/7-5/21= - (18+5)/21= -23/21= -1 2/21 ;

=== -29/7*(-12/29)===12/7=== 1 5/7 ;

===15/3÷(-7/39)= -15/3*39/7=-195/7= -27 6/7 .

Answer 2

Ответ:

$\\ 2 \frac{4}{9} - 3 \frac{5}{6} = \frac{9 \times 2 + 4}{9} - \frac{6 \times 3 + 5}{6} = \frac{22}{9} - \frac{23}{6} = \frac{18 \div 9 \times 22}{9 \times 2} - \frac{18 \div 6 \times 23}{6 \times 3} = \frac{44}{18} - \frac{69}{18} = \frac{44 - 69}{18} = \frac{ - 25}{18} = - \frac{25}{18} = - 1 \frac{7}{18} \\ \\ - \frac{6}{7} - \frac{5}{21} = - \frac{21 \div 7 \times 6}{7 \times 3} - \frac{5}{21} = - \frac{18}{21} - \frac{5}{21} = - \frac{18 + 5}{21} = - \frac{23}{21} = - 1 \frac{2}{21} \\ \\ - 4 \frac{1}{7} \times ( - \frac{12}{29} ) = - \frac{7 \times 4 + 1}{7} \times ( - \frac{12}{29} ) = - \frac{29}{7} \times ( - \frac{12}{29} ) = \frac{29}{7} \times \frac{12}{29} = \frac{29 \div 29}{7} \times \frac{12}{29 \div 29} = \frac{1}{7} \times \frac{12}{1} = \frac{1 \times 12}{7 \times 1} = \frac{12}{7} = 1 \frac{5}{7} \\ \\ 1 \frac{2}{13} \div ( - \frac{7}{39} ) = \frac{13 \times 1 + 2}{13} \times ( - \frac{39}{7} ) = - ( \frac{15}{13} \times \frac{39}{7} ) = - ( \frac{15}{13 \div 13} \times \frac{39 \div 13}{7} ) = - ( \frac{15}{1} \times \frac{3}{7}) = - (\frac{15 \times 3}{1 \times 7}) = - \frac{45}{7} = - 6 \frac{3}{7}$