Răspuns :
10 / 100 * A = 12
10 A / 100 = 12
10 A = 12 * 100
10 A = 1200
A = 1200 / 10
A = 120
10 / 100 * 120 = 0.1 * 120 = 12
10 A / 100 = 12
10 A = 12 * 100
10 A = 1200
A = 1200 / 10
A = 120
10 / 100 * 120 = 0.1 * 120 = 12
[tex]\displaystyle \frac{10}{100} \cdot r=12 \Rightarrow \frac{10r}{100} =12 \Rightarrow 10r=12 \cdot 100 \Rightarrow 10r=1200 \Leftrightarrow \\ \\ { \Leftrightarrow r= \frac{1200}{10} \Rightarrow \bold{r=120}[/tex]