Question

flying against the wind an airplane travels 3120 km in 6 hours flying with the wind the same plane travels 6440 kilometers in 7 hours what is the rate of the plane in still air and what is the rate of the way

Answer 1

The rate of plane in the air is 720km/hr and on the way is 200km/hr

Step-by-step explanation:

Let the rate of the plane be x;

Let the rate of the wind be y

If the plana fly in the direction of the wind then the speed will be x+y

If the plane flies in the opposite direction to the wind then the speed will be x-y

Using the expression;

Distance = Speed * Time

For the plane flying against the wind;

6(x-y) = 3120

6x-6y = 3120

x-y = 520 .......... 1

For the plane flying with the wind;

7(x+y) = 6440

x+y = 920 ............. 2

Add both expressions;

x+x = 520+920

2x = 1440

x = 1440/2

x = 720

Substitute x = 720 into equation 1

x - y = 520

720 - y = 520

y = 720 - 520

y = 200

This shows that the rate of plane in the air is 720km/hr and on the way is 200km/hr