Срочно плиз будте няшой
1)12 : 3 3/8 - 1 1/4 : 15/32
2)1 31/35 : (2 - 8/9 : 1 19/45)

1) $12:3 frac{3}{8}-1 frac{1}{4}: frac{15}{32}=frac{8}{9}$

$12:3 frac{3}{8}= frac{12}{1}: frac{3*8+3}{8}= frac{12}{1}*frac{8}{27}= frac{4}{1}*frac{8}{9} = frac{32}{9}$

$1 frac{1}{4}:frac{15}{32}= frac{1*4+1}{4}*frac{32}{15}= frac{5}{4}*frac{32}{15}= frac{1}{1} * frac{8}{3} = frac{8}{3}$

$frac{32}{9}-frac{8}{3}= frac{32-3*8}{9}= frac{32-24}{9}= frac{8}{9}$

2) $1 frac{31}{35} :(2- frac{8}{9} :1 frac{19}{45})=1 frac{13}{35}$

$frac{8}{9} :1 frac{19}{45}= frac{8}{9}: frac{1*45+19}{45}= frac{8}{9}* frac{45}{64}= frac{1}{1}* frac{5}{8}= frac{5}{8}$

$2- frac{5}{8}= frac{2}{1}-frac{5}{8}= frac{8*2-5}{8}= frac{16-5}{8}= frac{11}{8}$

$1 frac{31}{35} : frac{11}{8}= frac{1*35+31}{35}* frac{8}{11}= frac{66}{35}*frac{8}{11}= frac{6}{35}* frac{8}{1}= frac{48}{35}=1 frac{13}{35}$