Ma ajuta cineva si pe mine?

[tex]\it \mathcal{P}=2(L+\ell) = 2\Big(12\dfrac{3}{10}+\dfrac{2}{3}\cdot12\dfrac{3}{10}\Big)=2\cdot12\dfrac{3}{10}\Big(1+\dfrac{2}{3}\Big)=2\cdot\dfrac{123}{10}\cdot\dfrac{5}{3}=\\ \\ \\ =\dfrac{1230}{30}=\dfrac{123}{3}=41\ cm[/tex]