- Ta có : \(A+G=A+X=50\%N\)
- Do đó ta có hệ : \(\left\{{}\begin{matrix}A+X=50\%\\X-A=20\%\end{matrix}\right.\rightarrow\left\{{}\begin{matrix}A=T=15\%\\G=X=35\%\end{matrix}\right.\)
\(\rightarrow H-N=X\rightarrow4050-N=35\%N\rightarrow N=3000\left(nu\right)\)
\(\rightarrow L=3,4.\dfrac{N}{2}=5100\left(\overset{o}{A}\right)\)