Question

Найдите x в пропорциях:
Чётн.

Answer 1

$frac{3.25}{4x-1.9} = frac{13}{0.4} \ 13(4x-1.9)=0.4cdot3.25\ 52x-24.7=1.3\ 52x=1.3+24.7\ 52x=26\ x= frac{26}{52} \ x= frac{1}{2} \=================\ frac{1 frac{4}{5} }{2.5} = frac{7.2}{6x+1} \ frac{frac{9}{5} }{2.5} = frac{7.2}{6x+1} \ frac{1.8 }{2.5} = frac{7.2}{6x+1} \ 1.8(6x+1)=7.2cdot2.5\ 10.8x+1.8=18\ 10.8x=18-1.8\ 10.8x=16.2\ x=1.5\=================$
$frac{ frac{3}{8} }{0.75} = frac{0.6}{x-2.8} \\ frac{ 0.375}{0.75} = frac{0.6}{x-2.8} \ 0.375(x-2.8)=0.6cdot0.75\ 0.375x-1.05=0.45\ 0.375x=0.45+1.05\ 0.375x=1.5\ x=4$