\(N=\dfrac{2L}{3,4}=2400\left(nu\right)\)
Theo bài ta có hệ: \(\left\{{}\begin{matrix}A-X=20\%\\A+X=50\%\end{matrix}\right.\rightarrow\left\{{}\begin{matrix}A=35\%\\X=15\%\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}A=T=35\%N=840\left(nu\right)\\G=X=15\%N=360\left(nu\right)\end{matrix}\right.\)