Answer :
Answer:
Speed of plane in still air = 780 km/h
Speed of air = 52 km/hr
Step-by-step explanation:
Let the speed of plane in still air = u km/h
Let the speed of air = v km/h
Against the air, the resultant speed = (u-v) km/hr
With the air, the resultant speed = (u+v) km/hr
Formula for speed is given as:
[tex]Speed = \dfrac{Distance}{Time }[/tex]
Given that:
Distance = 5824 km
Time taken against the wind = 8 hours
Speed against the wind:
[tex]u-v = \dfrac{5824}{8} \\\Rightarrow u-v = 728 ...... (1)[/tex]
Time taken with the wind = 7 hours
Speed with the wind:
[tex]u+v = \dfrac{5824}{7} \\\Rightarrow u+v = 832 ...... (2)[/tex]
Adding (1) and (2):
[tex]2u=1560\\\Rightarrow u = 780\ km/hr[/tex]
By equation (1):
[tex]780-v=728\\\Rightarrow v = 52\ km/hr[/tex]
Speed of plane in still air = 780 km/h
Speed of air = 52 km/hr