A jet can travel the 6000 km distance between washington,

d. c. and london in 6 hours with the wind. the return trip against the same wind takes 7 hours 30 minutes. find the speed of the jet in still air and the rate of the wind.

d = r*t is the basic distance equation

d = 6000 km

t with the tail wind = 6 hr

r with the tail wind = speed of the plane + wind speed = s + w

t with the head wind = 7.5 hr

r with the head wind = speed of the plane - wind speed = s-w

(s+w) * 6 = 6000

(s-w) * 7.5 = 6000

s + w = 1000

s - w = 800

2s = 1800

s = 900 km/h

s + w = 1000

w = 100

Check the anwer by calculating the return trip.

(900-100) * 7.5 = 800 * 7.5

800 * 7.5 = 6000 km

Answer: The rate of the jet in still air is 900 km/h. The rate of the wind is 100 km/hr.