Question

Ответ на 270 . пожалуйста

Answer 1

$1) frac{25}{80} + frac{45}{60} = frac{5*5}{5*16}+ frac{3*15}{4*15}= frac{5}{4*4} + frac{3}{4} = frac{5+3*4}{4*4} = frac{17}{16} =1 frac{1}{16}$

2)
$frac{20}{45}+ frac{25}{54} = frac{5*4}{5*9}+ frac{25}{6*9}=frac{4}{9}+ frac{25}{6*9}= frac{4*6+25}{6*9} = frac{49}{54}$

3)$frac{36}{300}+ frac{12}{40} - frac{350}{1000} = frac{3*12}{25*12} + frac{3*4}{10*4} - frac{7*50}{20*50} = frac{3}{25} + frac{3}{10} - frac{7}{20} =$ $frac{3*4+3*10-7*5}{100} = frac{12+30-35}{100} = frac{7}{100} =0,07$

4) $frac{14}{24} - frac{39}{90} + frac{15}{100} = frac{2*7}{2*12}- frac{3*13}{3*30}+ frac{3*5}{20*5}= frac{7}{12} - frac{13}{30} + frac{3}{20} = [tex] frac{7*5}{12*5} - frac{13*2}{30*2} + frac{3*3}{20*3} = frac{35-26+9}{60}= frac{18}{60} = frac{3*6}{10*6} frac{3}{10} =0,3$

5)
$frac{42}{120}+ frac{20}{32}-frac{28}{160}=frac{6*7}{6*20} + frac{5*4}{8*4}- frac{7*4}{4*40}= frac{7}{20}+ frac{5}{8}- frac{7}{40}= frac{7*2}{20*2} + frac{5*5}{8*8} - frac{7}{40}=$$frac{14+25-7}{40} = frac{32}{40}= frac{8*4}{8*5}= frac{4}{5} =0,8$

6) $frac{45}{72}- frac{33}{144}- frac{20}{64}= frac{5*9}{8*9}- frac{3*11}{3*48}- frac{5*4}{16*4}= frac{5*6}{8*6}- frac{11}{48}- frac{3*5}{3*16}= frac{30-11-15}{48}= frac{4}{4*12}$$= frac{1}{12}$