The question should say The average speed of a van is 24 kilometers per hour faster ...
It is important to know that speed is measured in km/h.
The first equation to set up is simple.
v = 24 + t ( v is the speed of the van and t is the speed of the truck)
Now the second equation.
A good equation to remember is distance = rate * time
In 5 hours the van will travel 5*v kilometers
In the same manner the truck will travel 7*t kilometers
Since the problem says these distances are equal that is how we set up the equation.
5v = 7t
v = 24 + t
Simultaneously solve these equations.
