1) 2 1/7 : 1 11/14 2) 3 3/5 : 1 11/25 3) 1 7/9 * 2 2/5 : 1 3/5 4) ( 3 1/2 : 4 2/3 + 4 2/3 : 3 1/2) * 4 4/5 5) - 5,7 : (-19) - 0,8 * (-4) + 2,7 : 0,3 с подроб. решением

Ответ:

ellaandharley30

08.07.2020 01:43

1)
$2\frac{1}{7}:1\frac{11}{14}=\frac{7*2+1}{7}:\frac{14*1+11}{14}=\frac{15}{7}:\frac{25}{14}=\frac{15}{7}*\frac{14}{25}= \\ \\ =\frac{15}{1}*\frac{2}{25}=\frac{3}{1}*\frac{2}{5}=\frac{3*2}{1*5}=\frac{6}{5}=1\frac{1}{5}$

2)
$3\frac{3}{5}:1\frac{11}{25}=\frac{5*3+3}{5}:\frac{25*1+11}{25}=\frac{18}{5}:\frac{36}{25}= \\ \\ =\frac{18}{5}*\frac{25}{36}=\frac{18}{1}*\frac{5}{36}=\frac{1}{1}*\frac{5}{2}=\frac{5}{2}$

3)
$1\frac{7}{9}*2\frac{2}{5}:1\frac{3}{5}=\frac{9*1+7}{9}*\frac{5*2+2}{5}:\frac{5*1+3}{5}=\frac{16}{9}*\frac{12}{5}:\frac{8}{5}=\frac{16}{9}*\frac{12}{5}*\frac{5}{8}= \\ \\ =\frac{2}{9}*\frac{12}{5}*\frac{5}{1}=\frac{2}{3}*\frac{4}{5}*\frac{5}{1}=\frac{2}{3}*\frac{4}{1}*\frac{1}{1}=\frac{2*4}{3}=\frac{8}{3}=2\frac{2}{3}$

4)
$(3\frac{1}{2}:4\frac{2}{3}+4\frac{2}{3}:3\frac{1}{2})*4\frac{4}{5}=(\frac{2*3+1}{2}:\frac{3*4+2}{3}+\frac{3*4+2}{3}:\frac{2*3+1}{2})*\frac{5*4+4}{5}= \\ \\ =(\frac{7}{2}:\frac{14}{3}+\frac{14}{3}:\frac{7}{2})*\frac{24}{5}=(\frac{7}{2}*\frac{3}{14}+\frac{14}{3}*\frac{2}{7})*\frac{24}{5}= \\ \\ =(\frac{1}{2}*\frac{3}{2}+\frac{2}{3}*\frac{2}{1})*\frac{24}{5}=(\frac{3}{4}+\frac{4}{3})*\frac{24}{5}=(\frac{3*4+4*3}{4*3})*\frac{24}{5}= \\ \\ =\frac{24}{12}*\frac{24}{5}=2*\frac{24}{5}=\frac{48}{5}=9\frac{3}{5}$

5)
$-5,7:(-19)-0,8*(-4)+2,7:0,3= \\ \\ =-\frac{57}{10}:(-19)-\frac{8}{10}*(-4)+\frac{27}{10}:\frac{3}{10}= \\ \\ =-\frac{57}{10}*(-\frac{1}{19})-\frac{8}{10}*(-4)+\frac{27}{10}*\frac{10}{3}= \\ \\ =\frac{57}{10}*\frac{1}{19}+\frac{8}{10}*4+\frac{27}{10}*\frac{10}{3}= \\ \\ =\frac{3}{10}*\frac{1}{1}+\frac{8}{5}*2+\frac{9}{1}*\frac{1}{1}=\frac{3}{10}+\frac{16}{5}+9= \\ \\ =\frac{3+2*16+10*9}{10}=\frac{3+32+90}{10}=\frac{125}{10}=12,5$