d)
`3,16:(y-04)=7,9`
`y-0,4=3,16:7,9`
`y-0,4=0,4`
`y=0,4+0,4`
`→y=0,8`
b)
$\dfrac{y}{3}-\dfrac{2}{5}=\dfrac{1}{4}$
$\dfrac{y}{3}=\dfrac{1}{4}+\dfrac{2}{5}$
$\dfrac{y}{3}=\dfrac{5}{20}+\dfrac{8}{20}$
$\dfrac{y}{3}=\dfrac{13}{20}$
$⇒ y.20=3.13$
$⇒ y.20=39$
$⇒ y=39:20$
$→ y=1,95$
