Solution: Let us suppose there are m men and w women on bus.
Therefore, we have:
[tex]\frac{2}{3} =\frac{m}{w}[/tex]
[tex]w=\frac{3}{2} m[/tex]
Also we know that after 4 women got off, the ratio of men to women becomes 4:5
We can write:
[tex]\frac{m}{w-4}=\frac{4}{5}[/tex]
[tex]5m=4w-16[/tex] (cross multiplication)
[tex]5m=4\times \frac{3}{2}m -16[/tex] [tex]\because w=\frac{3}{2} m[/tex]
[tex]5m=\frac{12m}{2}-16[/tex]
[tex]5m=6m-16[/tex]
[tex]6m-5m=16[/tex]
[tex]m=16[/tex]
Therefore, there are 16 men on bus
