Question

(5⅗-1⅓):(7 7/12-2¼)
(2 ⅜+3 7/24):(4⅔-1⅛)

Answer 1

Ответ:

1) (5⅗-1⅓):(7 7/12-2¼)=

$(5\frac{3}{5}-1\frac{1}{3}) : (7\frac{7}{12}-2\frac{1}{4} ) =(\frac{5*5+3}{5} -\frac{3*1+1}{3} ):(\frac{12*7+7}{12} -\frac{4*2+1}{4} )=(\frac{28}{5} -\frac{4}{3} ):(\frac{91}{12} -\frac{9}{4} )=\\\\=(\frac{28*3-4*5}{15}} ) : (\frac{91-9*3}{12} )=(\frac{84-20}{15}} ) :(\frac{91-27}{12} )=\frac{64}{15}} :\frac{64}{12} =\frac{64}{15}} *\frac{12}{64} =\frac{1}{15}} *\frac{12}{1} =$

$=\frac{12}{15} =\frac{4}{5}$  или  $0,8.$

2) (2 ⅜+3 7/24):(4⅔-1⅛)=

$(2\frac{3}{8}+3\frac{7}{24}):(4\frac{2}{3}-1\frac{1}{8})= ((2+3)+(\frac{3}{8} +\frac{7}{24} )) : (\frac{3*4+2}{3} -\frac{8*1+1}{8} )=\\\\=(5+\frac{3*3+7}{34} ):(\frac{14}{3} -\frac{9}{8} )=(5+\frac{16}{24}):(\frac{14*8-9*3}{24} ) =5\frac{16}{24}:(\frac{112-27}{24} ) =5\frac{16}{24}:\frac{85}{24} =$

$=\frac{24*5+16}{24}:\frac{85}{24} =\frac{136}{24}:\frac{85}{24} =\frac{136}{24}*\frac{24}{85} =136*\frac{1}{85}=8*\frac{1}{5}=\frac{8}{5} =1\frac{3}{5}$  или   $1,6.$