PART 1. Going westward: Distance: 2400 miles Rate (this is speed): (450-wind_speed) mph Time: distance / speed = 2400 / (450-wind speed)
Going eastward: Distance: 2400 miles Rate (this is speed): (450+wind_speed) mph Time: distance / speed = 2400 / (450+wind speed)
PART 2 Formula for speed: speed = distance / time Now we solve this for time: time = distance / speed 11h = 2400 / (450+-wind_speed)
+- sign is put because in one case wind increases speed of plane and in other case it decreases speed.
PART 3 To solve for wind_speed we start by rearranging formula so that we have wind_speed on left side: (450+-wind_speed) = 2400 / 11 (450+-wind_speed) = 218mph To fly this distance in 11h speed of plane must be 218mph. The only way to get this solution is if we substract wind speed: 450-wind_speed = 218 wind_speed = 450-218 = 232mph
