Question

Помогите решить уравнения:
x/3.5=0.4/0.5
3/10=b/90
1.5/0.8=4.5/a

Answer 1

$\frac{x}{3,5}=\frac{0,4}{0,5}$
$0,5*x=0,4*3,5$
$0,5x=1,4$
$x=1,4:0,5$
$x=2,8$

$\frac{3}{10}=\frac{b}{90}$
$b*10=3*90$
$10b=270$
$x=270:10$
$x=27$

$\frac{1,5}{0,8}=\frac{4,5}{a}$
$1,5*a=4,5*0,8$
$1,5a=3,6$
$x=3,6:1,5$
$x=2,4$

Answer 2

1)2.8/3.5=0.4/0.5
2)3/10=27/90
3)1.5/0.8=4.5/2.4