Against the wind a commercial airline in South America flew 756 miles in 3.5 hours. With a tailwind the return trip took 3 hours. What was the speed of

Question

Against the wind a commercial airline in South America flew 756miles in 3.5 hours. With a tailwind the return trip took 3hours. What was the speed of the plane in still air? What was the speed of the wind?

Answer 1

Let x = the speed of the plane

let w = the speed of the wind

First find the speed of each trip. We know that speed is distance/time so:

 

Speed flying against the wind = x - w = 756/3.5 = 216 mph.

Speed flying with the wind is = x + w = 756/3 = 252 mph

 

Now you have a system of equations to solve using the elimination method

 

x - w = 216

x + w = 252

 

Combine these two equations to get

 

2x = 468

x = 468/2 = 234

 

Plug this answer back into either of the original equations to find w

 

x + w = 252

234 + w = 252

w = 252 - 234 = 18