Answer:
The speed of wind is 30 miles/hour
Speed of plane in still air is 108 miles /hour
Step-by-step explanation:
Distance traveled by plane to Bangkok = 1794 miles
The trip there was with the wind. Time taken = 13 hours.
The trip back was into the wind. The trip back took 26 hours.
Let s = plane speed in still air
let w = speed of the wind
(s+w) = speed of plane with wind
(s-w) = speed of plane against wind
Distance = Speed * Time
When the trip was with the wind .
⇒
⇒
⇒ ---1
When The trip back was into the wind.
⇒
⇒
⇒ ---2
Add 1 and 2
⇒s+w+s-w =138+78
⇒2s =216
⇒
⇒
To find w substitute the value of s in 1
⇒
⇒
⇒
Thus the speed of wind is 30 miles/hour
Speed of plane in still air is 108 miles /hour