Taking into account the definition of speed, the average speed of the trip is 428.57 [tex]\frac{km}{h}[/tex] .
First of all, it is necessary to know that speed expresses the relationship between the space traveled by an object and the time used for it.
In other words, speed can be defined as the amount of space traveled per unit of time with which a body moves. That is, speed is associated with the change in position of a body over time and can be calculated using the expression:
[tex]speed=\frac{distance traveled}{time}[/tex]
In this case, you know that an airplane travels at a speed of 300 [tex]\frac{km}{h}[/tex] for 2 hours. So the distance can be calculated as:
[tex]300 \frac{km}{h} =\frac{distance traveled}{2 h}[/tex]
distance traveled= 300 [tex]\frac{km}{h}[/tex]×2 h
distance traveled= 600 km
On the other side, the airplane speeds up to 400 [tex]\frac{km}{h}[/tex] for the next hour. So the distance traveled is:
[tex]400 \frac{km}{h} =\frac{distance traveled}{1 h}[/tex]
distance traveled= 400 [tex]\frac{km}{h}[/tex]×1 h
distance traveled= 400 km
Finally, the airplane travels the final 4 hours at a speed of 500 [tex]\frac{km}{h}[/tex]. So the distance can be calculated as:
[tex]500 \frac{km}{h} =\frac{distance traveled}{4 h}[/tex]
distance traveled= 500 [tex]\frac{km}{h}[/tex]×4 h
distance traveled= 2000 km
Then, you know that the total distance traveled and the total time for this trip is:
Replacing these values in the speed definition:
[tex]speed=\frac{3000 km}{7 h}[/tex]
Solving:
Speed= 428.57 [tex]\frac{km}{h}[/tex]
In summary, the average speed of the trip is 428.57 [tex]\frac{km}{h}[/tex] .
Learn more about average speed:
