Đặt mA = a (tấn); mB = b (tấn)
Giả sử a + b = 1 (tấn) (1)
\(m_{Fe_2O_3\left(A\right)}=a.60\%=0,6a\left(tấn\right)=6.10^5a\left(g\right)\)
=> \(n_{Fe_2O_3\left(A\right)}=\dfrac{6.10^5a}{160}=3750a\left(mol\right)\Rightarrow n_{Fe\left(A\right)}=7500a\left(mol\right)\)
\(m_{Fe_3O_4\left(B\right)}=b.69,6\%=0,696b\left(tấn\right)=696.10^3b\left(g\right)\)
=> \(n_{Fe_3O_4\left(B\right)}=\dfrac{696.10^3b}{232}=3000b\left(mol\right)\Rightarrow n_{Fe\left(B\right)}=9000b\left(mol\right)\)
\(n_{Fe\left(tổng\right)}=\dfrac{0,48.10^6}{56}=\dfrac{60000}{7}\left(mol\right)\)
=> \(7500a+9000b=\dfrac{60000}{7}\) (2)
(1)(2) => \(a=\dfrac{2}{7}\left(tấn\right);b=\dfrac{5}{7}\left(tấn\right)\)
=> \(\dfrac{a}{b}=\dfrac{2}{5}\)