a, \(X_2=G_1=145\)
\(G_2=X_1=215\)
\(A_2=T_1=135\)
\(T_1=\dfrac{0,15.N}{2}\Rightarrow N=\dfrac{2T_1}{0,15}=\dfrac{2.135}{0,15}\Rightarrow N=1800\)
\(\Rightarrow T_2=A_1=\dfrac{1800}{2}-145-215-135=405\)
b, \(A=T=A_1+A_2=135+405=540\)
\(\Rightarrow\%A=\%T=\dfrac{540}{1800}.100\%=30\%\)
\(G=X=G_1+G_2=145+215=360\)
\(\Rightarrow\%G=\%X=\dfrac{100\%-2.30\%}{2}=20\%\)