Answer:
Explanation:
Let the speed of plane is p and speed of the wind is w.
Then we have:
- 10*(p + w) = 1120 ⇒ p + w = 112
- 20*(p - w) = 1120 ⇒ p - w = 56
Sum the two equations and solve for p:
- p + w + p - w = 112 + 56
- 2p = 168
- p = 84
Find w:
- 84 + w = 112
- w = 112 - 84
- w = 28