Question

Помогите решить уравнения (все)p.s.На фотографиях

Answer 1

$frac{1}{ frac{1}{28} + frac{1}{36} } = 1: ( frac{1*9+ 1*7}{252} ) = 1 : frac{16}{252} = 1 : frac{4}{63} = 1* frac{63}{4} = 15 frac{3}{4} = 15,75$


$( frac{4}{13} - frac{3}{26} )* frac{39}{5} = frac{4*2-3}{26} * frac{39}{5} = frac{5*39}{26*5} = frac{1*3}{2*1} = 1 frac{1}{2} =1,5$


$( frac{7}{50} - frac{5}{36} ) : frac{2}{9} = frac{7*18 - 5*25}{900 } * frac{9}{2} = frac{126-125}{900} * frac{9}{2} = frac{1*9}{900*2} = frac{1}{200}$


$3 frac{1}{25} : (1 frac{5}{14} - 1 frac{4}{15} ) =3 frac{1}{25} : ( frac{19*15-19*14}{210} ) = frac{76}{25} : frac{19}{210} = frac{76*210}{25*19} = \ \ = frac{4*42}{5*1} = frac{168}{5} = 33,6$


$2 frac{16}{17} : ( frac{1}{34} + 1 frac{5}{18} ) = frac{2*17+16}{17} : frac{1*9 + 23*17}{306} = \ \ = frac{50}{17} : frac{400}{306} = frac{50}{17} : frac{200}{153} = frac{50*153}{17*200} = frac{1*9}{1*4} = 2 frac{1}{4} =2,25$