Let rate of faster bus be x km/h and rate of slower bus be y km /hr.
The relation between rate of slower and faster bus is,
[tex]x=y+12[/tex]Two bus are travelling in opposite direction so relative speed is,
[tex]x+y[/tex]Two buses meet in 6 hours so,
[tex]\begin{gathered} (x+y)\cdot6=1404 \\ x+y=234 \end{gathered}[/tex]Substitute y + 12 for x in the equation to obtain the value of y.
[tex]\begin{gathered} y+12+y=234 \\ 2y=234-12 \\ y=\frac{222}{2} \\ =111 \end{gathered}[/tex]Determine the value of x.
[tex]\begin{gathered} x=111+12 \\ =123 \end{gathered}[/tex]So answer is,
Rate of faster bus is 123 km/hr
Rate of slower bus is 111 km/hr.