Problema Solution
Against the wind a commercial airline in South America flew
360
miles in
2.5
hours. With a tailwind the return trip took
2
hours. What was the speed of the plane in still air? What was the speed of the wind?
Answer provided by our tutors
let
d = 360 miles the distance traveled in one direction
t1 = 2.5 hours the time of the flight against wind
t2 = 2 hours the time of the return trip (with the wind)
w = the speed of the wind
v = the speed of the plane in still air
v - w = the speed of the plane flying against the wind
v + w = the speed of the plane flying with the wind
since speed = distance/time we have
v - w = d/t1
v - w = 360/2.5
v + w = d/t2
v + w = 360/2
by solving the system
v - w = 360/2.5
v + w = 360/2
we find:
v = 162 mph the speed of the plane in still air
w = 18 mph the speed of the wind
click here to see the step by step solution of the system of equations: