Question

Let the speeds of the cars starting from ( A ) and ( B ) be ( x mathrm{km} / mathrm{hr} ) and ( y mathrm{km} / mathrm{hr} ). respectively According to problem,
[
begin{array}{l}
9 x-90=9 y
frac{9}{7} x+frac{9}{7} y=90
end{array}
]
Sciving we get ( x=40 mathrm{km} / mathrm{hr} ., y=30 mathrm{km} / mathrm{hr} . )
speed of car ( A=40 mathrm{km} / mathrm{hr} & ) speed of car ( B=30 mathrm{km} / mathrm{hr} ).

# COPILULUI VOR Points A and B are 90 km. apart from each other on a highway. A car starts from A and another from B at the same time. If they go in the same direction, they meet in 9 hrs. and if they go in opposite directions, they meet in 9/7 hrs. Find their speeds.

Solution