Answer:
1 hour
Step-by-step explanation:
The distance covered by each of the two vehicle can be written as
[tex]d=vt[/tex]
where
d is the distance covered
v is the speed of the vehicle
t is the time elapsed
For the bus, the speed is
[tex]v_b = 60 mph[/tex]
So the distance covered by the bus in a time t is
[tex]d=60t[/tex] (1)
The kids in the bus took 3 hours to reach the camp,
t = 3 h
So the distance between the school and the camp is:
[tex]d=(60)(3)=180 mi[/tex]
For the truck, the speed is
[tex]v_t=45 mph[/tex]
So the distance covered by the truck in a time t is
[tex]d=45t[/tex] (2)
Since the distance to cover is 180 miles, the time taken by the truck is
[tex]t=\frac{d}{45}=\frac{180}{45}=4 h[/tex]
And so, the truck arrives
[tex]\Delta t = t_t - t_b = 4 h - 3 h = 1 h[/tex]
1 hour after the bus.
