SOLUTION: With a tail wind, Brittany's helicopter traveled 300 miles in 1 hour 40 minutes. The return trip against the same wind took 20 minutes longer. Find the wind speed and the air speed

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: With a tail wind, Brittany's helicopter traveled 300 miles in 1 hour 40 minutes. The return trip against the same wind took 20 minutes longer. Find the wind speed and the air speed      Log On


   



Question 920346: With a tail wind, Brittany's helicopter traveled 300 miles in 1 hour 40 minutes. The return trip against the same wind took 20 minutes longer. Find the wind speed and the air speed of the helicopter.
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Helicopter speed =x mph
wind speed given speed =y mph
against wind speed given 2 hours
with wind speed given 1 2/3 hours

Distance against 300 miles distance with 300 miles
t=d/r against wind speed given -
300.00 / ( x - y )= 2.00
2.00 ( x - y ) = 1.67
2.00 x - 2.00 y = 300.00 ....................1

300.00 / ( x + y )= 1.67
1.67 ( x + y ) = 300.00
1.67 x + 1.67 y = 300.00 ...............2
Multiply (1) by 1.67
Multiply (2) by 2.00
we get
3.33 x + -3.33 y = 500.00
3.33 x + 3.33 y = 600.00
6.67 x = 1100.00
/ 6.67
x = 165.00 mph

plug value of x in (1) y
2.00 x -2.00 y = 300.00
330.00 -2.00 -330.00 = 300.00
-2.00 y = 300.00
-2.00 y = -30.00 mph
y = 15.00
Helicopter speed 165.00 mph
wind speed given speed 15.00 mph

m.ananth@hotmail.ca