Answer:
- Option A
- Speed of plane is 240 km/h, speed of wind is 50 km/h
Step-by-step explanation:
With the tail wind the total speed is the sum of the speeds of plane and wind.
When into wind the total speed is the difference of speeds of plane and wind.
The first equation is
The second equation is
Simplify both equations and solve the system
- r + w = 1740/6 ⇒ r + w = 290
- r - w = 570/3 ⇒ r - w = 190
Solve by elimination, add up the equations
- r + w + r - w = 290 + 190
- 2r = 480
- r = 240
Find the value of w
- 240 + w = 290
- w = 290 - 240
- w = 50
