Question

вычислите а)35 умножить(421+27)=

Answer 1

$frac{3}{5} ( frac{4}{21} + frac{2}{7} )= frac{3}{5} ( frac{4}{21} + frac{2*3}{7*3} )= frac{3}{5} ( frac{4}{21} + frac{6}{21} )= frac{3}{5} frac{4+6}{21} = frac{3*10}{5*21}= frac{1*2}{1*7}= frac{2}{7}$