Answer:
speed of plane in still air = 252 mph
speed of wind = 42 mph.
Explanation:
Given:
Distance travelled by the small plane = 245
Time taken to fly 245 miles = 1 hour and 10 minutes.
Time taken for return trip = 50 minutes.
To Find:
speed of the wind=?
The speed of the plane in still air=?
Solution:
We Know that
[tex]speed = \frac{distance}{time}[/tex]
=>[tex]\frac{245}{ \frac{70}{60}} hours[/tex]
=>[tex]\frac{245}{ \frac{7}{6}} hours[/tex]
=>[tex]245 \times { \frac{6}{7}[/tex]
=>210 mph against wind
on way back
=>[tex]\frac{245}{ \frac{50}{60}} hours[/tex]
=>[tex]\frac{245}{ \frac{5}{6}} hours[/tex]
=>[tex]245 \times { \frac{6}{5}[/tex]
=> 294
Now
294 = plane +wind------------------------(1)
210 =plane - wind-------------------------(2)
Solving (1) and (2)
2 plane = 504
plane = 252
plane = [tex]\frac{504}{2}[/tex]
So substituting plane value in eq(2) we get,
210 =252 - wind
wind = 42 mph